Often, humans in live-action children's shows will all be The Danza, but Imagination Movers has two Scotts, so one of them takes the character name "Smitty".
Michael Showalter and Michael Ian Black are frequent collaborators and often use their own names in their projects, leading to various humorous situations.
In Stella, the three main characters are roommates named Michael, Michael, and David. In one episode, they write a novel entitled The Three Guys about three roommates named Michael, Michael, and Craig.
Black and Showalter currently star in Michael and Michael Have Issues.
MTV: In the late 1980s and early 1990s, this network had two different women named Julie Brown hosting shows on the network, although one of them (the one who was black, British and subsequently did Playboy) usually went by the name "Downtown Julie Brown."
Reality TV (and other Game Shows) can often go both ways on this - early series of Big Brother UK, given two people of the same first name, would make one adopt a pseudonym - Paul and Bubble in series 2, or Anoushka and Nush in 4. However in series 10, Sophie, Sophia and Saffia became a running joke very early on.
Rachael and Rachel appeared in Series 11- although one was the first evictee, and the other was a late entrant about half way through, so they never appeared in the house at the same time as one another.
The fall 2012 season of The Amazing Race had "James and Jaymes" as one team, and yet another person named James on a different team.
Starting from season 7, America's Got Talent had an unusual situation with both Howie Mandell and Howard Stern as judges. Technically it's the same name, but since one always goes by "Howie" and the other "Howard", it never caused any problems.
When this sort of show has been running for decades, and has a list of characters numbering in the hundreds, the writers have to get creative, and sometimes fail. Days of Our Lives featured a character named "Patch" - because he wore an eyepatch.
However, One Life to Live took advantage when the writers discovered they had duplicated a last name. Todd Manning was given that last name because it sounded masculine. Years earlier, Manning had been established as the last name of Victor Lord's mistress. The writers later decided that it was the same Manning, and Todd was Victor's son.
On the topic of ABC soaps, since all three are in-house productions, with a handful of exceptions and special examples, there are never two characters (on contract status) with the same first name on any of the three shows at the same time.
In General Hospital, there's Lucas Lorenzo Spencer and his son of the same name. Though it is true no two will be called the same name at the same time: Here the elder goes by "Luke" and the younger goes by "Lucky" (There was also a Lucas Jones, named after the elder Luke). On the same show, there's Mike Corbin, his son Michael "Sonny" Corinthos, and his son, Michael Corinthos III. The eldest Mike has been scarce since the youngest Michael has gotten more screen time.
The Bold and the Beautiful seem to be the exception. Almost every child born gets their name from a relative on the show. A few examples: Bridget (a combination of Brooke + Ridge), Nicole (named after Nick), Dominic (also named after Nick, whose full name is Dominic), Jack (named after grandma Jackie and Taylor's dad Jack), Steffy (actually Stephanie Jr), Mary (named for her grandmother), Rick (whose actual name is Eric Jr), Eric III (Rick's son). In addition, Storm's actual name is Steven Jr, after his dad (who features on the show at times).
And there are even more examples: CJ's full name is Clarke Junior, Baby Logan was named after his grandmother's family name, Alexandria is named after her father's ex wife (Macy Alexander), there are three generations of William Spencer, Rosie is named after her mother (Amber, whose full name is Ambrosia)...
Similarly, As the World Turns has Chris Hughes who shared the name with his now deceased grandfather. His brother Casey was named after their mother's half-sister's father Casey Peretti.
This trope often turns up in British soap operas:
Brookside had two characters in the series at the same time with the same name, albeit using different spellings: Jacqui Dixon and Jackie Corkhill. The two were seldom confused. The background to this: an existing character, Jimmy Corkhill, was given an off-screen wife called Jackie in the late 1980s. In 1990, the Dixon family moved in, with the daughter called "Jackie" (name spelt as such on the show's End Credits) - but the following year, the producers decided to make Jackie Corkhill an on-screen character; hence "Jackie Dixon" quickly became "Jacqui Dixon". The show also had Mike Dixon and Mick Johnson at the same time.
At one point in Coronation Street's history, there were three members of staff at the Rovers Return with the birthname Elizabeth but all using different short forms of the name; Bet Lynch (the nameplate above the front doors referring to "Elizabeth Teresa Lynch"), Betty Turpin (a previous landlady called her "Elizabeth" to differentiate between her and Bet) and Liz Mc Donald (often called Elizabeth by her husband). Today, there's only Betty and Liz who remain behind the bar at the Rovers. At her wedding, Elizabeth was also revealed to be Maureen Holdsworth's middle name.
For a very brief while during 2010, there were two Jacks in Coronation Street: Jack Duckworth - a long serving character who was killed off in the series that year - and Jack Dobbs, a baby born and named in honour of the other Jack a few months before the elder one's on-screen death.
The first two episodes featured guest character Elsie Lappin as well as regular Elsie Tanner.
While in EastEnders, there have been many cases of two characters having the same or similar names appearing in the show at the same time: Billy Mitchell and Billy Jackson (latterly spelt Billie), Steve Owen and Stephen Beale - and in the same family, the Slaters, there was Big Mo and Little Mo.
Australian soap opera Home and Away has had a couple of characters named Jack and Joey (one of the Joeys was female). But the real example? An arc in late 2009 has two characters named Ruby. One is (or was) involved with Xavier, and the other is his retarded brother's girlfriend.
24: Avoided recycling names for a while, but eventually gave up. There were two characters of different genders who shared the same name: Lynne Kresge in season 2 (Michelle Forbes) and Lynn McGill in season 5 (Sean Astin).
Mainstay judges Jay Manuel and J Alexander avoids this by respectively being referred to as mister and miss before their first names.
Two pair of winners of the show ran through this. Cycle 11 winner Brittany "McKey" Sullivan and Cycle 16 winner Brittani Kline avert this, but Cycle 5 winner Nicole Linkletter and Cycle 13 winner Nicole Fox plays this straight.
Two runner-ups are named Laura. They are Laura Kirkpatrick from Cycle 13 and Laura LaFrate from Cycle 18.
And leave us not forget those in the same season.
Averted, but taken to the extreme in Cycles 18's Ashley, AzMarie, and Kyle, two of whom took on nicknames for the One Ashley Limit.
The same case happened in Cycle 11 with ShauRon, Brittany and winner McKey. In this case, two girls took nicknames for the One Brittany Limit.
In Cycle 20, Bianca "Kanani" Andaluz and Bianca Alexa avert this, but Chris Hernandez and Chris Schellenger plays this straight.
Lucille Bluth's best friend/rival was named Lucille Austero. This mostly resulted in problems for Buster, who was the son of one Lucille and briefly dated the other. For example, he once bid on the wrong Lucille at a bachelorette auction. The narrator handled this by referring to Lucille Austero either by her full name, or as Lucille Two.
Also 'Loose Seal!'
This show in general disregarded this convention. Character names included George, Michael, George Michael, Oscar, and George Oscar (though he went by his initials).
Bad Girls: Had two main characters both named Julie, who were best friends and had gone to jail at the same time. Tina O'Kane briefly changed her name to Julie as well, but then later went back to her original name.
Ballykissangel: An unusual example occurs in the BBC series , where a shady politician previously named Sean Dooley returns in the fifth season as Paul Dooley, presumably so the viewers won't confuse him with the then-leading-man Sean Dillon.
Band of Brothers: Justified Trope for being historically accurate, where we the main cast includes two Joes - Liebgott and Toye (there's also Joe Domingus, but he's a tertiary character) - and two Donalds (Malarkey and Hoobler). Additionally, there are several secondary characters named John ("Cowboy" Hall, Father Malone, Janovec and "Peewee" Martin). Since most characters are usually referred to by their last name anyway, this rarely becomes a problem.
Battlestar Galactica (Reimagined): This show gives us Billy Keikeya, Bill Adama (who we learn, conveniently after Billy's death, was also called Billy - but only in his youth, decades before Keikeya's birth), the one episode character William "Willie" King, and of course, Liam Tigh.
A slightly odd semi-aversion: Spike's original name was William, and Angel's original name was Liam (which is the Irish version of William). Plus, there's Willy, who runs the demon bar, and Willow, who is frequently called Will. The nickname for William, Billy, was used for at least three one-episode characters: Billy Palmer ("Nightmares") and Billy "Ford" Fordham ("Lie to Me") on Buffy, and Billy Blim ("That Vision Thing" and "Billy") on Angel.
Also, Anne is Buffy's middle name which she occasionally goes by, the adopted name of Anne Steele, the name of Spike's mother, and one of Drusilla's sisters.
One episode of Angel had Knox, the vampire who turned Gunn's sister. Knox was also the name of a scientist who worked for Wolfram & Hart in season 5.
Burn Notice has broken this rule a few times with Tom Strickler and Tom Card, as well as Tyler Brennen and Tyler Gray. Lampshaded when Michael talks to a "Samantha", Sam Axe assumes that he is talking to him.
Actually had three Billys. The first was a one-episode character in season 1. The second was a character in Phoebe's favourite movie. The third (Billie this time) was a season regular in season 8.
The Halliwell line also has a number of recurring names. Melinda Warren was their ancestor and was what Piper named her daughter in the future. There was also another Prudence in the Halliwell line, whom Prue was evidently named after.
Cheers averted this for a joke in the episode where Sam's Corvette is stolen. After hearing a customer has also had a rare car stolen, Sam decides to form a support group for people who've had rare cars stolen. He gets to know them by what cars they've lost. When he has to address another member of the support group by name, he admits he's not good with names. It turns out the other support group member is also named Sam.
Has two Davids. Assistant coroner David Phillips is sometimes referred to as Super Dave, while the lab tech is only ever called by his surname, Hodges.
Doc Robbins' first name was also 'David' before they changed it to 'Al'. Probably aided by the fact that he is played by Robert "David" Hall, so it kinda goes along with Super Dave Phillips being played by David Berman and Archie Johnson who is played by Archie Kao.
Also CSI:NY's Lindsay Monroe and CSI:Las Vegas' Catherine Willows' daughter, Lindsey.
One episode used the aversion of this trope as an actual clue, when several seemingly-unrelated crimes' victims or suspects happened to have pets named "Gareth". Turned out they all knew the same con artist, who'd named the pets after his brother.
The Daily Show: For several years the cast included a Steve Carell and a Stephen Colbert. They actually had a debate skit called "Even Steph/ven". Now they include many correspondents named "John" - John Hodgman, John Oliver, and of course the host himself, Jon Stewart. There were also Rob Corddry and Rob Riggle.
Dallas: Had three characters named 'John Ross' - the family patriarch, his eldest son and that son's son. In the show only the youngest was ever called 'John Ross', while his father (John Ross II) always went by the name 'JR' and the grandfather (John Ross I) by the name 'Jock'.
Deadliest Catch: Has the brothers Josh and Jake Harris of the Cornelia Marie, as well as another Jake on the Northwestern. Interestingly, both Jakes have similar foofy hair and cocky attitudes, and their captains ponder "switching Jakes" for a season. There's also a cameraman named Jake (or was it Josh?) who almost died of seasickness-induced dehydration while on the Cornelia Marie and is good-naturedly chided by the Harrises when he's forced to use a suppository.
Dexter: In the fourth season, the title serial killer pretends to be someone named Kyle Butler to insinuate himself into the life of another serial killer, Trinity, as a consequence of which Trinity tracks down and kills a random, innocent Kyle Butler. It's complicated.
All this said, the surnames "Jones" and "Smith" are disproportionately common in the Russell T Davies era:
Jones: Harriet, Ianto, Martha. Jo Grant can be included since she took her husband Clifford's name on marriage. Also Eugene from the DW spinoff Torchwood.
In the teleconference scene in The Stolen Earth", three of the participants are named Jones: Harriet, Ianto, and Martha. And another's Smith (Sarah Jane).
The Adventure Games with the Eleventh Doctor and Amy has a computer quarantining an underwater base called Jones.
Smith: Sarah Jane, Mickey, and the Doctor's traditional alias of John Smith, plus Sarah Jane's familynote son Luke, daughter Sky, and "extraterrestrial supercomputer" Mr Smith and Mickey's parallel-universe counterpart Ricky. Also, Adam Smith in one episode of Torchwood, who also shares his first name with a short-term companion of the Ninth Doctor. Lampshaded in "Journey's End" when Mickey takes down a Dalek that was about to kill Sarah Jane, and quips, "We Smiths have to stick together."
According to episode credits, Martha became Mrs Smith-Jones after her marriage to Mickey.
Of course, it is completely coincidental that the Eleventh Doctor was played by the real-life Matt Smith. Or is it?
In one story arc, Big Finish used two characters called Amy and Zara. After the Eleventh Doctor's first companion was called Amy, the Big Finish character has been renamed to Abby.
The Whoniverse now has two "R. Williams": Rhys and Rory.
We have a cyborg one-shot villain working for the Cybermen as well as member of Sanctuary Base 6 under demonic possession called Tobias (Vaughn and Zed).
Jamie, the long-time companion of the Second Doctor, is also the name of the eponymous Empty Child.
The show has three monarchs called Elizabeth (the two historical ones and a future Elizabeth X) as well as Queen Victoria, who share names with Dr. Liz Shaw and Victoria Waterfield.
We have two Angela Prices in the Whoniverse, a freedom fighter against the Cybermen in a parallel universe, and the descendant of someone who helped Sarah Jane find a piece of Chronosteel in The Sarah Jane Adventures.
A hologram newsreader in New Earth as well as a one-shot character that faced the Weeping Angels was called Sally.
The scared boy in "Night Terrors" and the security guard from "Closing Time" are both called George.
There's Lucy Hayward, one of the Minotaur's victims in "The God Complex", and the Master's wife, Lucy Saxon. Lucy Hayward's surname was "Miller" in the original script; possibly the change was to avoid confusion with the Big Finish companion Lucie Miller.
The show has quite a few Thomases and Tommys. There's Tom, from The Smugglers, Tommy, from The Green Death, Tommy Connolly, from "The Idiot's Lantern", Thomas Kincade Brannigan, from "Gridlock" Thomas Milligan, from "Last of the Time Lords", and Tommy Brockless in the Torchwood episode "To the Last Man". There is also the double offender Thomas Thomas from "The Crimson Horror."
Jenny is a woman inhabited by the Family of Blood, the Doctor's daughter, and one of the Doctor's army at Demon's Run (who is also the maid/lover of Vastra the Silurian) as well as a freedom fighter in The Dalek Invasion of Earth and a companion in one of the stage plays.
The ultimate villains in "The Greatest Show In The Galaxy" were named as the Gods of Ragnarok. The following season, "The Curse of Fenric" used many themes from Norse mythology, but the author was not allowed to refer to Ragnarok by name due to this trope.
In "A Town Called Mercy" the Doctor meets a horse called Susan, which is also the name of his granddaughter.
In a curious meta example, none of the Doctors' actors shared a given name (although Tom and Colin were both Bakers, and Jon (Pertwee) and John (Hurt) come close) until Peter Capaldi (sharing a given name with Peter Davison).
A minor character in "Nightmare in Silver" was called Missy, the same name as a major character from the following series. This was pointed out to Mark Gatiss in a Q/A, and his reaction caused some Epileptic Trees.
Frobisher is the name of a shapeshifting Sixth Doctor companion, and John Frobisher is a villain in Torchwood: Children of Earth. note The latter was the one played by Peter Capaldi, in case you were confused.
There is an unrelated villain called The Master in "The Abominable Snowman", though it is just a title for The Great Intelligence. There is also a character in "The Mind Robber" called The Master, though he is not a villain.
The Second Doctor had a string of comics starring a Cyberman companion called Kroton. He also fought monsters called the Krotons in "The Krotons".
A species of monster called a Varga plant shows up in "Mission to the Unknown"/"The Daleks' Master Plan". The lead Ice Warrior in "The Ice Warriors" is named Varga.
Jenny - Barbara's friend and a member of La Résistance in "The Dalek Invasion of Earth", the Doctor's daughter in "The Doctor's Daughter" and Jenny Flint, the maid and wife of Vastra.
Downton Abbey: Technically has two servants named Thomas and two named Alfred, but due to servant naming convictions one Thomas is Branson and one Alfred is Mr. Molesley. In season 3, one of the Thomases has left service and is now "Tom", but Thomas has been promoted and is now "Mr. Barrow", so it's still good.
Early Edition, Gary tries to propose a toast to a certain George Muzakis in order to find the guy and save him quickly, and a dozen or so with that name stand up because it's a family reunion.
The Following has an episode in which one of the killers targets women named Claire Matthews, also the name of the cult leader's ex-wife. It's a subversion of this trope, although no one openly says, "That's odd, I've met several Claires but I'm the only Ryan in the world!"
Foyle's War: Glaringly uses "Hauptmann" as the maiden name of two different German expatriate women married to upper-crust Englishmen. "Greenwood" also shows up as the surname of one character, the alias of another, and the name of a farm.
Frasier: Mildly averted, where Daphne consistently addressed both Niles and Frasier as "Doctor Crane" for many seasons.
Friends: After dating Ross, Rachel dates a guy called Russ, also played by David Schwimmer.
Full House: This was an Averted Trope and played around with. Stephanie mentions that she is going to a different school than her friends, all of which were named Jennifer, and were differentiated by last initial. (Jennifer C. went to this school, Jennifer S. went to that school.) Little Michelle, who was so young at this point she was barely able to string a sentence together, turns to Stephanie and says, "Maybe you'll meet a new Jennifer."
Gilmore Girls: Strictly speaking, there were three Lorelai Gilmores - Lorelai Gilmore the mother, Lorelai "Rory" Gilmore the daughter, and Lorelai "Trix" Gilmore - Rory's great grandmother (and yes, her maiden name was Gilmore too).
There are two Davids (Jerk Jock/ Armoured Closet Gay Dave Karofsky and Warbler David) and two Andreas (Andrea Cohen from Vocal Adrenaline and Rod's co-anchor Andrea Carmichael).
As of mid-season 3, there are now a third David: David Martinez, the night school Spanish teacher.
The season two episode ''Britney/Brittany gives us Britney Spears and Brittany S. Pierce.
Tina Cohen-Chang shares her last name with both her boyfriend, Mike Chang, and the aforementioned Andrea Cohen.
Also, Kurt and his dad Burt.
And Finn and Quinn, who were a couple in the beginning of season 1 and then again for a while in season 2.
Averted in The Good Wife with the introduction of Carey Zepps, a lawyer working alongside Cary Agos, one of the main characters. Though not spelled the same, their names are pronounced the same.
Goodnight Sweetheart: Played with this a couple of times, as the main theme of the show was that Gary Sparrow tried at all costs to avoid his 1940s mistress, Phoebe, and his 1990s wife, Yvonne, discovering his time-travelling escapades. In one episode, the arrival of "Yvonne" is announced in the 1940s pub of which Phoebe is the landlady, but this turns out to be an aunt of Phoebe's. In another episode, Gary tracks down a 1990s "Phoebe Sparrow", but, as the lady in question is black, she cannot be the girl he fell in love with (and possibly married) in the 1940s.
Growing Pains: Used this to allow Mike's girlfriend Kate to read a love note his grandfather had written to his grandmother Kate.
Head of the Class: Played with this an Arvin started an ARVIN CLUB, and even met an attractive girl named Inga Arvin.
Heartbeat: When this show added PC Steve Crane to the regular cast, they apparently forgot that an earlier episode had established supporting character Jenny Latimer as having a brother called Steve. Steve Latimer ended up coming back for Jenny's wedding while Steve Crane was on the show. It's not all that noticeable until the closing sequence when they start appearing in the same scenes.
Hells Kitchen: Season 8 had Lewis and Louis (pronounced "Louie"). Lewis subverted this trope by going by his last name, Curtis. Didn't matter much, as both were eliminated very early.
Mined this for a gag, when the Show Within a Show had three generations of Al Unsers as guests, in addition to Tim's assistant Al Borland. Things got confusing real quick when Tim tried to interview Al. (Which one? Exactly.) At the end of the episode, the three Al Unsers were back wearing T-shirts labeled "Big Al", "Little Al", and "Norm-Al"; and Tim pulled out an "Abnorm-Al" shirt for Borland - but Al (B.) opened his flannel shirt to reveal that he already had a "Speci-Al" T-shirt.
We also find out that Al had a brother named Cal, which is probably meant to poke at this trope.
Then we learn their mother's name...Alma.
Homicide: Life on the Street: Had two Mikes: Kellerman, and Gee's FBI agent son. The latter was introduced after the former had been written off, but they met in a two-part arc and the reunion movie.
Hot Potato: The Bee Keepers team consisted of Tim 1, Tim 2 and Glen.
House: Averted, where we have two secondary characters named Rachel: Taub's wife and Cuddy's baby daughter.
Two characters named Tasha have appeared on the show. The first in the season 1 episode iNevel, and a recurring love interest for Gibby in Season 3, in the episode iSpeed Date. Two Chuck's have appeared, with one being a delivery man and the other an evil little boy. Two Brads have appeared on the show. One was a big-shot producer of TVS (iCarly Saves TV), and the other brought the fudge (iHire an Idiot, iOMG).
Then in iParty WithVictorious, they break the Trope Name, by having Carly's boyfriend named Steven, just like Carly's father.
In 1996, Michael Dupee and Michael Daunt were two of the finalists. Dupee went by "Mike" to differentiate himself.
Similarly, the 2008 Teen Tournament somehow ended up with two Rachels in the finals. One of them decided to go by "Steve".
Joan of Arcadia: Rather oddly averted, where we get the next best thing to The Other Darrin with the Deadpan Snarker bookstore owner Sammy. In season two we get a different actor with the same name, job, and personality, yet he's established as a different person who took over the position from the first Sammy. Joan even notes how coincidental it is.
Justified: While the names of main characters, like Boyd and Raylan haven't been used more than once, several minor character names have been recycled. The most prominent has to be Nicholas and its variants. We've had asshole police officer Nick Moony, paranoid conspiracy theorist and former pimp Nicky Kush, and Detroit mob bagman Nicky Augustine. Kush and Augustine even briefly meet face to face when Augustine accompanies Boyd to interrogate Kush.
Kamen Rider Den-O: This show, which uses Time Travel as a central conceit, ran headlong into this with its first movie, where the 10-year-old version of Ryotaro joins up with the group. To avoid confusion, the group refers to the younger as Kotaro (as in, "Little Ryotaro"). For extra fun, a later movie introduces another Kotaro, this time Ryotaro's Grandkid from the Future.
Kenan & Kel: Natural born Kenan involves the duo heading to the records department for Kenan's birth records, to prove whether or not he's adopted. However, he gets the wrong record by mistake - he gets the birth record of Kevin Rockmore, who was born to parents George and Margaret Rockmore in the same hospital and on the same day as Kenan, who was born to parents Roger and Sheryl Rockmore. They then think that Kenan had been switched at birth. In the end, Kevin and his parents are revealed to be Asian and of no relation to the African-American Kenan.
Had a song/sketch titled "These Are the Daves I Know" in which the singer names a dozen or so people in his life who answer to David or Dave.
The "Thirty Helens Agree" sketches, featuring 30 Helens standing in a field.
Cathy and Kathie, the secretaries.
The two Geralds, rival businessmen.
The King of Queens: In the episode "Better Camera", Arthur shows guest star Lou Ferrigno a screenplay he wrote. Lou is confused by the fact that several characters are named Mike. Arthur explains it by asking if Lou has ever met someone else named Lou and then claims his screenplay is "true to life".
Law & Order and its various spinoffs: There have been a number of characters, both major and minor, named Serena and Alexandra.
Lead Balloon: In one episode, self-centred misanthrope Rick Spleen gets a part as Eddie in a series called "All About Eddie"; one of his friends asks if he's sure that he is the Eddie the series is all about.
Rick: No. That'd— why would there be two people called Eddie? That'd be stupid.
Rick:(on phone to director) So yeah, are there two people called Eddie, or...?
In addition to Steve who survived the crash, there was another Steve on board who was killed. The show reuses names frequently: there have been several Brians, Toms, Anns, Richards, Adams, and other common names, which makes the already Epileptic Tree theories worse (see below):
Not to mention the constant, in-universe confusion between two characters named Scott and Steve. When one died, it actually increased the confusion, as the deceased had to be identified by name. It's made even worse by the actor playing Steve playing Scott's body, and the actor playing Scott continuing to appear on the show afterward as a nameless extra. Or maybe I switched those.
'David' also crops up frequently, being the first name of Libby's deceased husband, Charlotte's father, Jack's son (in the flash-sideways) and is particularly meaningful to Hurley, as his father and imaginary friend share the name. Oh, and it's also Desmond's middle name. Showrunner Damon Lindelof has mentioned that it's probably a subconscious Freudian issue of his, as his own father is named David.
Then we have Charlie Pace, Charlie Hume (Desmond and Penny's son), Charles Widmore, and Charlotte Lewis
It is likely that Jack was actually born Jonathan Shephard meaning that he and John Locke have the same name. I always assumed that it was done on purpose to further their dichotomy. It was, however, never mentioned on the show, so its canonicity is questionable at best.
Mad Men: Aversion in season 5: protagonist Don Draper hires a black receptionist named Dawn. Roger Sterling calls her "darkest before the Don."
Major Crimes: Captain Raydor discovers a little too late that she has the same first name as Rusty's mother. When she tells him that he can call her Sharon instead of Captain Raydor, he at first thinks it's some sort of cruel joke, and then gets mad because if she didn't even know that she had the same name as his mother, then she's obviously not looking for her like she promised him she was.
Mash: Had John McIntyre, known as Trapper John, and John Black, known as Ugly John. Also, in the book, the movie, and the beginning of the series, Father Mulcahy's first name is John, although later in the series it was established as Francis. (M*A*S*H had a few problems remembering its characters' names over its 11-year run. Col. Blake's wife, Lorraine, was on multiple occasions called "Mildred", which probably influenced the decision to make that Col. Potter's wife's name.)
Both Trapper and Frank Burns had wives named Louise.
Then there's the plethora of background nurses given the same generic surnames like "Able" and "Baker".
Played with in the episode where Hawkeye is mistakenly getting mail belonging to a different Capt. Benjamin Pierce.
Men Behaving Badly: In one episode, Gary, Tony, Dorothy and Debs stay on a campsite and meet someone else called Tony. They refer to him as "Tony Too".
Merlin: There have been two Tristans, the first a Monster of the Week and the second one half of the famous Tristan and Isolde pairing. Since the characters appeared four seasons apart, there's virtually no chance of getting them muddled up.
Modern Family has two secondary characters named Pam, which becomes more confusing since they're both primarily connected to Cameron's story-lines and are deliberately named to echo him: one Pam is his sister, the other is the lesbian mom to a boy at Lily's school who is basically Cam's Distaff Counterpart.
Although apparently "Pam" stands for different things in both cases. When Cam calls his sister by her full first name (seemingly in all seriousness), it's Pameron. Mitchell is the only one who seems to think it's weird.
The Monkees: Ran into this when they had the cast use their real names on the show and two of them, Micky Dolenz and Mike Nesmith, had variations of the same first name. Ironically, neither actually has the first name Michael. Their real names are George Michael Dolenz and Robert Michael Nesmith.
Inverted Trope in the Bruces sketch. The faculty of the Philosophy Department of the University of Woolamaloo are all named Bruce, and when a new instructor named Michael joins, they call him Bruce to avoid confusion.
It's also important to note they had two guys named Terry.
Several of the sketches in the series had characters named Arthur.
Not only did Erics feature in many sketches, but the Fish License sketch featured Eric Praline talking to Eric the Postal Clerk about a license for his pet halibut, Eric, in addition to the license he has for his cat, Eric, his dog, Eric, and his fruit-bat, Eric. When Eric refuses to give Eric a license for Eric, Eric asks for a license for Eric the half a bee, whom Eric asks Eric the orchestra leader to sing about.
Moving Wallpaper: Accidentally averted in this show about TV writers. In the first series the writing staff included an assistant named Kelly, who Carl, one of the writers, was in love with. In the second series the star actress of the show they're working on is Kelly Brook. This even confused some TV reviewers, with one summarizing an episode as "Carl pines for Kelly Brook".
Gibbs at first makes this an Invoked Trope in "Jurisdiction" by refusing to call visiting CGIS agent Abigail Borin 'Abby', out of respect for Abby Sciuto. However, in a later episode, "Ships in the Night", he congratulates a joint effort by the pair by saying "Abbs-es - that is good work."
One episode averts this trope for comic effect, with a DEA drug dog called Tony, leaving the DEA agent waiting for Tony to finish going over the boat so that Tony can go over the boat.
Also averted with Tony and his dad, who both have the first name Anthony.
Tony again: in one episode, Anthony was the name of the victim's husband.
Tony: Married her high school sweetheart, Anthony. Nice name.
One episode had two Leroy Jethros in it, as Gibbs was named after a childhood friend of his father.
The New Adventures of Old Christine: The premise is an aversion of this trope. In addition to Old Christine and New Christine, there's also Richard and his son, Ritchie. Old Christine's maiden and married surnames sound very similar, which is pointed out in the episode when she decides to change her surname to the hyphenated hybrid "Kimball-Campbell." And there is an episode when she tries to get back together with an ex-boyfriend Burton only to discover he has a new girlfriend, Christine, who Old Christine dubs "Pretty Christine."
Newhart: "I'm Larry, this is my brother Daryl, and this is my other brother Daryl."
The New Statesman: One episode features a crony of Alan's named Piers, the same as his regular-cast sidekick/flunky. "Ah. It appears we have two Piers."
NTSF:SD:SUV: Features a computer technician named Sam and a robot named S.A.M. as regular characters, although the robot is always referred to as "Ess Ay Em." One of the roboticists who created S.A.M. is Aaron Samson, who also insists on being called "Sam", and shares a scene with Sam and S.A.M. in one episode.
NYC 22: Aversion used for a throwaway gag in the pilot. Rookie officer Tonya Sanchez has trouble finding her locker because there are at least two other Officer Sanchezes in her precinct. Played straight among the main cast, however.
Erin's first name is actually Kelly, the same as Kelly Kapoor, who initially attempts to use it to her advantage in flirting with Charles Miner. Erin quickly volunteers to go by her middle name and the matter is never brought up again.
We also have Robert California, the company's new CEO, and Robert Lipton, Angela's senator husband.
The British show had characters named Dawn and Donna.
Parks and Recreation: Ron has ex-wives called Tammy One and Tammy Two, and his mother's named is Tamara (Tammy for short).
Person of Interest: Subverted. Two main characters share the name 'Samantha.' Though, to be fair, they are typically addressed by their hacker codename (Root) and surname (Shaw) respectively.
Popular: Two characters had the name Mike: One had it as his real name, while preferring to use his nickname "Sugar Daddy", while the other had it as his nickname, with his real name Michael.
Austin St. John who plays Jason Lee Scott was born Jason Geiger.
In Power Rangers Megaforce, Yellow and Pink are called Gia and Emma respectively. The previous season had Yellow and Pink being called Emily and Mia repectively. So not only did they have similar names, they also swapped their colours. 6 episodes in and some fans are still confusing them.
Primeval: Has two Toms. One is a main character who is blond, stocky and in the SAS; the other is one of Those Two Guys ginger, lanky, and a geeky conspiracy theory nut. They both die in the first series.
Raising Dad: Acknowledged this in an episode once as Sarah had an Evan, Erin and Aaron at the house for dinner and Emily stammered on the names a couple of times.
Aversion: an uncommonly large number of guest characters have the first name Frank. There's Frank Hollister (the captain of Red Dwarf), Frank Todhunter (the second officer), Frank Rimmer (Rimmer's older brother), Rimmer's uncle Frank (mentioned only), Frank Saunders (in the novel Infinity Welcomes Careful Drivers, Saunders was the hologram before McIntyre's death), the guy called Frank who found baby Lister under the Aigburth Arms pool table, and in one episode Kryten mentions that he named the washing machine Frank because "he works better with an identity".
"Lemons" does this as well. Turns out there were a lot of people named Jesus in AD 23, and the one the Dwarfers assist is just an ordinary guy.
Remember WENN: In-universe example: Betty has to give feedback to a writer who has named both the hero and villain of her script "John." This is especially confusing because it's on radio.
Revolution: Averted Trope. There's Jacob the bounty hunter ("Chained Heat") and Jacob Renn the Monroe militia guy. There's Joseph Deckert the Monroe militia captain ("Ghosts") and Joseph Wheatley the Monroe militia mole ("Kashmir"). There's Pete Bowers the Monroe militia major ("The Love Boat") and Peter the young man ("The Children's Crusade"). There's Richard Lucas the Georgian Navy officer and Richards the Monroe militia private ("No Quarter"). There's Rose the housekeeper of the Nevilles and Fabers ("Ties That Bind"), and Rose/Rosie the rebel ("The Song Remains the Same"). There's Steve the insurance adjuster boss ("Soul Train") and Steve the bounty hunter ("Home"). There's Trevor the rapist outlaw ("Pilot") and Trevor the rebel ("No Quarter"). There's Beth Robinson-Bromley a name in a file and Beth the wife of Jane Warren ("The Night the Lights Went Out in Georgia"). There's John Sanborn the scientist ("Clue") and John Faber the Monroe militia colonel. There's Amy Tipton a name in a file and Amy Wilkes the Plains Nation girl ("The Longest Day"). There's George the rebel and George Maya a name in a file. There's Doug Meerdinx and Doug Sloan who are both names in a file. There's Billy Frank a name in a file and Billy Underwood the bully. There's Sean the Pittman's friend ("Sex and Drugs"), Sean Bozeman a name in a file, and Sean Miller the newspaper producer. There's David Kipling the former Monroe militia major ("Nobody's Fault But Mine"), David Moxness a name in a file, and David Stockton a name in a file.
Jane's father and brother are both named Frank, though her brother goes by Frankie.
Also, when Jane's other brother, Tommy, has a baby, they name him Tommy Junior (T.J. for short).
Rome: The creators of this TV series did their best to neaten up everyone's names (since Real LifeAncient Rome averted this trope horribly), but they were still left with siblings Octavian and Octavia, and Vorenus's two daughters Vorena and Vorena.
Roseanne: An early episode revealed that DJ's real name was "David Jacob." Later, a completely different David eventually joined the show (and eventually became DJ's brother-in-law, no less).
Sanctuary: This Canadian sci-fi show likes to re-use names. There are two Edwards; two families with the similar last name Meyers and Myers; Joe and Josephine, who are both HAPs; another Joe, Joseph and Josie; a Lilian and a Lillian. Even the names of two of the main characters, Helen and Henry, are oddly alike.
The Sarah Connor Chronicles: Has both John Connor, humanity's future savior, and John Henry, a rudimentary AI controlling a Terminator endoskeleton. However, John Henry is always referred to by his full name, limiting any possible confusion.
One episode has a character called Murray. To prove a point he yells out his name and a crowd of old men poke their heads out the door.
J.D.'s brother is named Dan, and one of J.D.'s exes is named Danni, who dated another guy named Danny at one point. This confused J.D. when he thought Danni was calling out her own name in bed.
One of JD's interns in nicknamed Cabbage (his real name is Jason Cabbagio) and another has Cabbage as his last name. The real Cabbage is nicknamed Wolfman to avoid confusion and because he looks like a werewolf.
JD and Dr. Cox both have girlfriends named Julie, though not at the same time.
Seinfeld: Jerry attempts to find a conversation starter for when he meets Jerry Lewis. George says he doesn't need a conversation starter because they have the same name.
Sherlock: Unless they rename The Dragon, this BBC series is going to have two characters named Sebastian.
Skins: Averted in several instances. In addition to Jim Stonem (Tony and Effy's father),the second generation had both James Cook and James Fitch, twins Katie and Emily's younger brother. Of course, one of the writers is Jamie Brittain, although there is no obvious Author Avatar. Also, in the first series, Cassie's fellow patient at the therapeutic treatment centre ("Water Bottle Girl") is sometimes credited as Katie. The sixth series had two Al's-Alo and Alex (they're even referred to as Al 1 and Al 2 occasionally in Skins Lock-in). Alex shares his name with a hanger-on "conceptual artist" who appears in Cook's series 4 episode. The show has featured Franky's two dads, Geoff and Jeff. There have been Elizabeth Jenkins (Sid's mum), Pandora's Aunt Elizabeth, and Elizabeth "Effy" Stonem. "Beth", the Manic Pixie Dream Girl in Tony's series 2 episode may be another if she is an actual person, although many fans see her as Tony's subconscious manifestation of Effy. All the men in Sid's extended family, with the exception of Sid and his father, Mark, have names which are variations of "Alexander". She may be a Shelley, but one of the chav girls who beat Sid up in his series 1 episode is called "Shell", as is Michelle. Thomas Tomoni shares a name with the tutor Tom. Averted by Skins: Fire, where a different character named Freddie goes by without comment.
Soap: The final season featured the revolutionary El Puerco, whose group of guerrilla fighters is almost completely wiped out, leaving only Juan, Juan, and Juan. After the requisite name confusion jokes, they started to become known as Juan One, Juan Two, and Juan Three, though this was hardly necessary as Juan Two and Juan Three disappeared without an explanation shortly afterwards.
Sometimes there's a good (familiar) reason two characters would share a first name (like being cousins who were both named after the same older relative, or something like that). Often they would have nicknames, though there were two characters with the nickname "Pussy" (I think one was never actually seen though, or only in the first season or something, before he got whacked, but it's been a while). However, sharing first names and using odd nicknames, when it comes to The Mafia, is definitely Truth in Television.
One was 'Big Pussy', the other was 'Little Pussy'.
This was lampshaded in the first episode, when there was a discussion about killing "Little Pussy" and somebody thought they were talking about "Big Pussy".
Well at the very least there was Anthony (Tony) and Anthony Junior (AJ), not to mention Jackie Aprile and Jackie Jr.
Mobsters love this convention. Within the same show we also have Bobby Junior, Vito Junior, Carmine Junior, Patrick Parisi Junior, 'Little Ricky' Aprile, and, of course, Corrado Soprano Junior. Paulie's protege "Little Paulie" also deserves mention.
Not to forget Tony Soprano and Tony Blundetto, with one episode even being called 'The Two Tonys'.
So You Think You Can Dance Australia: Semi-aversion in the current series, which has, in the top twenty competitors, Jess, Jessie, and Jessica.
Stargate SG-1: Had the nametags of many random extras reading "Davis". Major Davis was a recurring character who worked for the government, but the Engaging Chevrons guy had his nametag say Davis for ages before his name was revealed as Walter Harriman. Confusing.
The trope is inverted, where there was a prominent, long-time recurring character named Bobby Singer. In the episode "The French Mistake" the main characters are catapulted in an alternative version of reality where they need to pretend to be the actors (Jared & Jensen) who are playing them (the characters Sam & Dean). Upon discovering the fictionalized (and actual) TV show Supernatural is produced by Robert Singer:
Sam: So the character in the show, Bobby Singer...
Dean: What kind of a douche-bag names a character after himself?
Sam: Oh, that's not right.
There are also at least two people named Jimmy, Anna (and one Annie), and Mary. There is also an angel named Samandriel, which is close to Sam (who is named after his grandfather,Samuel).
Rachel is both Sam's prom date and the name of an angel.
There were two Russells in Survivor Samoa: Russell Hantz and Russell Swan. Hantz lasted longer in the game and was known as "Evil Russell" by the fanbase because of his puppet-master style of play. Yet after Swan was medevacked from the game, fewer people bothered to make the distinction between them. The finale made it even less of an issue; there was so much talk about how Hantz ended up losing that whenever someone said the name "Russell," it was generally assumed they were talking about "Evil Russell."
Also, the two Robs in Survivor All-Stars. Rob Mariano was (and still is) known as "Boston Rob," and Rob Cesternino was called "Rob C.," "Cesternino," or his full name. There were also two Jennas. The other Jenna quit early so it was generally averted.
Rob Mariano actually dealt this in Marquesas (his original season) with Robert DeCanio, which is the very reason he became Boston Rob in the first place. The latter was referred to as "The General".
Survivor Nicaragua had "Coach" Jimmy Johnson (yes, the same) and Jimmy T., who was sometimes called "J.T." Those nicknames spill over into One Steve Limit with Tocantins and Heroes vs. Villains players Benjamin Wade and James Thomas Jr., who are never called anything but "Coach" and "J.T." Aside from the two Jimmies, this season also had Kelly Bruno and "Purple" Kelly Shinn.
Blood vs. Water has Laura Boneham and Laura Morett, as well as John Cody and John Broward "Brad" Culpepper.
This Is Wonderland: Has two unrelated characters with the last name "Davis". Anthony is a successful and handsome defense attorney. Rosemary is a hideous and monumentally stupid crackhead.
Time Slip: In order to preserve the surprise, and also maintain the One Steve Limit, Liz's counterpart in the various potential 1990 time zones has changed her name to Beth. Simon is less lucky, and is known in the future as 2975.
Touching Evil: In the original UK version, the main character's name is David Creegan, and the first episode of the second series features a character named David Laney. In the US remake, Laney's first name was changed to Stephen.
A Touch of Frost: In addition to regular character Detective Sergeant George Toolan, the episode "True Confessions" features a solicitor also named George. In the episode "Not With Kindness", a suspect called George Compton appears.
In addition to the three-names-for-Henry's-six-wives thing (see Real Life section), quite a few male characters are named Thomas. All of this is justified by the historical setting.
Though they got around the three Katherines by calling them Katherine, Kitty and Kate, respectively. And the Thomases are almost invariably referred to by their last names or titles (Wolsey, More, Cromwell, Cranmer, etc.) to avoid confusion.
Twin Peaks: Had Laura Palmer's boyfriend Bobby and his best friend Mike who shared names with the show's Big Bad Bob and his one-armed accomplice, Mike. There's also Sheriff Harry Truman and Harold Smith.
The War At Home: On the first day of the school year, Larry decides to reinvent himself to become more popular, and so starts going by the name of Gideon. At the end of the episode he goes back to being Larry, because it turns out there's an Israeli transfer student named Gideon. The real Gideon apparently thought Larry was mocking him, and kicked his ass for it.
Both Josh's therapist and the psychologist they send him from ATVA are called Stanley.
Additionally, the speechwriting interns assigned to Will Bailey are named Lauren, Lauren, Lauren, and Cassie. He eventually gives them Washington Redskins jerseys just so he can get them straight.
C.J.'s press room seems to be full of people named Chris, at least one of whom is a woman. Also, in "Debate Camp" during the flashback to when she's new on the job and is memorizing who sits where, the list includes "... Julie, Julie, Julia..."
Aaron Sorkin likes to reuse names, which can result in jarring examples of this; for example, there's a season two episode with a character named "Bruno" and a character named "Gianelli"— Bruno Gianelli is the campaign manager in season 3. And how many people do you know with the last name "Tascano"? Charlie knows at least two.
A senator named Stackhouse is mentioned in a season-one episode in a list of names of politicians who are liable to accuse the White House of being soft on drugs even though they themselves have used their influence to smooth over drug arrests for family members. In the fourth season, we're introduced to Stackhouse as an idealistic and conscientious statesman who would never do a thing like that (and whose pet project is needle exchange programs to protect heroin addicts from AIDS, not something a politician is likely to support if he cherishes a reputation for being hard on drugs). Presumably Sorkin had forgotten Stackhouse was no longer a blank slate.
Stackhouse also appears in the 2nd season episode "The Stackhouse Filibuster," as a Senator with an autistic grandson who filibusters an important piece of legislation re: children's health in order to secure funding for autism research.
Santos' assistant Ronna is first named in an amusing scene lampshading the similarity with Donna's name, and the confusion that can result from One Steve Limit violations when you introduce yourself with just "hi, Ronna". Of course, Donna had been on the show since the beginning, so no viewers were confused.
of course that did not stop it from confusing the two characters when they first met and continuously assumed that when one said their name they were attempting to correct the former in their own name.
Early on in the series, Kathryn Joosten was asked what her character's first name should be ( as she was always on a Last Name Basis with the cast); she settled on Margaret. This was vetoed, as there already was a fairly significant character named Margaret (Leo's secretary), so she was given the name Dolores.
Whose Line Is It Anyway?: Usually (unintentionally) played straight...but averted by the fact that there are four Steves. (In order: Stephen Fry, Steve Steen, Steve Frost, and Stephen Colbert.) Also, there have been three Kathys, although none have appeared at the same time.
Simultaneously included no less than five recurring characters named Michael/Mike, who had no direct connection to one another and never met: Michael Lee the teenager, Mike Fletcher the Baltimore Sun reporter, Michael Santangelo the Western District cop, Michael Steintorf the mayor's chief of staff, and Jimmy McNulty's son Michael. If you want to count very minor characters, there was also a drug dealer named "White Mike" who showed up briefly in season 2, and Omar calls out to a "Mike" in season one when he's dealing drugs off his own corner.
"The Greek's" was the name of a restaurant/game arcade in season one, and "The Greek" was the Big Bad of seasons two and five. As far as we know, there is no connection between the two at all.
Averted with regularity on this show. Dennis "Cutty" Wise and Dennis Mello; Roland "Wee-Bey" Brice and Roland Pryzbylewski; William "Bunk" Moreland and William Rawls; Tommy Carcetti, Thomas "Herc" Hauk and Thomas "Horseface" Pakusa; Johnny Weeks and Johnny "Fifty" Spamanto; Ray Cole and Raymond Foerster.
The X Factor: Series 7 had Louis Walsh, judge in every series so far, and Louis Tomlinson, member of Boy BandOne Direction. Both names are pronounced the same way (lew-y), so it can get confusing for new fans of the band following their worldwide breakthrough who are unfamiliar with the show and watch their X Factor performances for the first time on YouTube when the boy band member Louis starts talking about how the judge Louis would dance like a grand-dad and then starts demonstrating. The fact that every X-Factor fan calls both Louis's by their first name just makes it worse.
There were two brothers in The X-Files with the same name, though not in the same episode.
Mulder's father was called 'Bill', as is Scully's older brother. Later Scully and Mulder's child is named William, after Mulder's father.
Even more extreme than that - Scully's brother Bill is named after their father: both of the main characters' fathers are named William. Thus bringing the grand total of Williams in the series just in Mulder and Scully's immediate families to four.
It should also be noted that Agent Diana Fowley has an unusually similar first name to Dana Scully, in TV terms.
Yo soy Betty, la fea: In this Colombian soap that spawned Ugly Betty, the heroine Beatriz (called "Betty" by her family) discovers early on that the relative who owns the company she now works at is named "María Beatriz". The latter wonders how they'll be able to tell each other apart, despite her being a fashion-conscious plastic surgery addict, and Betty being a woman with poor fashion sense who's convinced she's ugly.