One hundred teenagers are sent to the ground, unsupervised, to test if the planet is survivable again. Even Clarke and Wells, who had parents on the governing Council, were not exempted. That they sent their children to what would probably be their deaths is a source of angst for parents and children alike.
Raven says her mother was "AWOL" for most of her childhood, and no mention is made of her father; she considers her Childhood Friend, Finn, to be her real family.
Absolutely Fabulous: Subverted/parodied. In one episode, a central lady character learns of a sister she never knew of before, and they meet. They end up talking about their mother, and it turns out she was a sexual monster. One sisters claims she "sprinkled illegitimate children all over Europe" and both remember her catchphrase, whenever she had given birth: "take it away, and bring me another lover!" It is heavily suggested that the fathers were never known. Neither of the sisters hold grudges for their mother or invoke angsty childhood.
Alias: During the first season we learn that Sydney's mother apparently died in a car accident when she was six. However, at the end of the Season 1 finale we learn that she faked her own death and now leads a criminal organization. Upon meeting Sydney for the first time as an adult, she proclaims, "You must have known this day would come. I could have prevented all this, of course. You were so small when you were born. It would have been so easy.".
All in the Family: In the ninth-season opener, Edith's chronically drunk cousin, Floyd, leaves his daughter Stephanie on their doorstep and leaves (presumably to get help, find work or go on his drinking binges). Although Floyd does appear from time to time — continuing into Archie Bunker's Place — to regain custody of (or make contact with) Stephanie, he in fact has "abandoned" her ... and by early 1981, Archie (who by now is widowed) has been granted full custody of Stephanie.
Angel: Most of the characters' parents, except for Fred's (who stand out by being loving and responsible), are MIA. Angel/Angelus ate his, Gunn's are never mentioned, Cordelia's are in jail for tax evasion; Wesley's mom is in England, with his emotionally abusive father; Spike turned his mother, but had to kill her when she turned out to be a worse monster than he was, and Lorne's parents live in another dimension — plus his father is probably dead, and his mother hates him. Much love.
Felicity Smoak's father left her mother and her when she was a child. His disappearance is ominously alluded to multiple times in season three, to the point that he is on his way to becoming the Mysterious Parent.
Shortly after Sara (apparently) died on Gambit, Dinah Lance divorced her husband, left her remaining daughter, moved to another city, and made little to no effort contact with Laurel over the next 5 years. When she does appear, it's usually about Sara suggesting Parental Favoritism.
Between Sara's apparent death and Dinah Lance divorcing him, Quentin Lance became an alcoholic. While still present in Laurel's life, it's indicated he wasn't there emotionally, and instead she was largely forced to take care of him.
The A-Team: Face wandered into an orphanage after being abandoned at five years old, he knows neither parents. Murdock's mum died when he was five years old and no mention is ever made of his father. BA has a mother but no mention is given of what happens to his dad.
Battlestar Galactica (1978): Starbuck was orphaned at a very young age during a Cylon attack. However, it is discovered in the episode "The Man with Nine Lives" that an aging con-man Chameleon happens to be Starbuck's biological father.
Bear in the Big Blue House: The unstated rule seems to be "we just don't talk about it." Some of the kids have grandparents, but Treelo seems to have nobody at all other than Bear, and Tutter apparently lives in the Big Blue House.
Beetleborgs: At first you'd think it's this, as Roland's dad and grandmother are main characters but there's no sign of a mom. However, eventually, the dad leaves the show and is replaced by the mom. (They're only seen at the comic book shop run by he grandmother, so presumably it was just a change of jobs and they're still together.)
Beyond: After Celeste's death, Frost had zero interest in Willa. This is why Arthur - her grandfather - ended up raising her.
The Big Comfy Couch seems to have the same unstated "we just don't talk about it" rule as Bear in the Big Blue House. Even though Loonette is apparently a child, she lives alone with her doll Molly, and while she has a grandmother, aunt and uncle, no parents are ever seen or mentioned. In the episode "Where Do Clowns Come From?" we learn that baby clowns float down from the sky, so it's possible she never had any parents at all.
Bones: This is said to be one of the reasons behind Bones' retreat to hyper-rationality and cutting herself from forming emotional attachments. Also in the backgrounds, in various ways, of Booth (abused by his alcoholic father, raised by his grandfather) and Sweets.
Boy Meets World: Happens to Shawn several times over. First by his mother, then by his father, then by his mother again, then his father again...
Buffy and Dawn's father is in Spain with his secretary, while Xander's parents (drunken and always fighting) and Willow's mother (too clinical) put in one episode-only appearances. Willow's father is only referred to. Tara's mother is dead and her father is a bastard (as are her brother and cousin). Anya's parents have been dead for over 1000 years. Fortunately, Giles serves as father figure for the whole gang.
Connor in Season 9. Angel refuses any contact with him, even ignoring his phone calls, because he thinks it will be better for him. Connor's fake family, the Reillys, have lost all memories of him as a result of the magic being gone, so he's left without a father figure.
Twilight is a bit upset by the fact that Angel and Buffy abandoned it to return to their own dimension.
Charmed: Paige was abandoned by her parents at a church because of fear from the Elders.
Prue, Piper, and Pheobe's father left them, either because he couldn't handle being married to a witch or because their grandmother pushed him out of their lives (it varies from episode to episode). They eventually manage to reconcile with him, but it takes several seasons.
Chuck: Chuck and Ellie Bartowski's mother left when Chuck was in fifth grade, and their neglectful father finally up and left as well about ten years later. They learned to get along with just each other to rely on.
Defiance: Amanda was forced to raise her little sister Kenya after their mother was killed during the war. It turns out that Amanda was with her mother scavenging for supplies when the war got close to where they were. Their mother wanted to simply run and wasn't willing to back and get Kenya. When Amanda insisted that they do so, mom simply left without either of them.
Dexter: The title character was raised by a good, caring foster family. He didn't care about his biological family for the most part, until weird things bring them up. Namely his biological brother, whose existence he had all but forgotten, kills their father, and tries to get Dex to kill his foster sister. During the course of the first season, Dexter remembers being witness to the brutal chainsaw killing of his mother, which helps explain why he and his bro are so screwed up. During the second season, he learns that it was his foster father who essentially unintentionally put his mother in the position that got her killed. Not only that, but his foster dad killed himself when he realized grooming Dexter to become a model serial killer wasn't exactly a good idea. His foster father also wouldn't let his real father raise him, judging him as not being good enough.
Doc Martin: The Ellinghams took every opportunity to not have to raise Martin, sending him to boarding school at age six and having him spend summers with Aunt Joan (until his father decided that Joan was too immoral). Louisa's mother walked out on the family when she was ten and she became estranged from her gambling-addict father when she was an adult. Her father eventually becomes a criminal, causing a second estrangement. Her mother returned to become a cast member in season 5.
Some of the companions: Vicki, Dodo, Jamie, Sarah Jane, and Adric are orphans, Victoria's mother is dead and in her first story her father gets exterminated, Nyssa's mother is dead and in her first story her father is killed and his body hijacked by the Master, Ace's father is never mentioned and likely out of the picture, Rose's father is dead (though not for lack of trying to prevent it), and both of Mickey's parents walked out when he was very young and his grandmother, who raised him, died tripping on a damaged piece of carpet on the stairs he never got around to fixing. Naturally, he feels very guilty about this. We also find out (in his final episode) that Turlough's mother was killed during a civil war on his planet, his father and stepmother were sent to a prison planet and killed when their transport crashed, whilst he was exiled to a boarding school on earth.
For the duration of Series 5, Amy's parents had never existed due to the time-crack in her house. Amy herself doesn't realize this until the end, shortly before the Doctor undoes the damage caused by the cracks.
Urkel's parents leave unannounced to live in Russia, forcing the Winslows to take him in. As a Running Gag had it that his parents were never really fond of him, Urkel is not really bitter or resentful.
Later episodes, revolving around cute kid 3J joining the Winslow household, established that 3J was abandoned by his mother when he was a baby. (Carl does take 3J to meet a waitress, to help him explain that someday, his mother will be willing to meet with her son; only Carl is aware that the waitress is 3J's biological mother, and she shows gratitude and is relieved that 3J will be raised in a stable household.)
A variation occurs, where the Tam siblings' parents send River to a government-sponsored Academy that proceeds to wreck her mind while experimenting on her. When Simon tries to explain to them what is happening, they show increasingly less interest in River's welfare, to the point that their father threatens to disown Simon if he continues causing trouble trying to reach her, which he eventually does before Simon rescues River. It is up in the air as to whether or not this is simply callous abandonment by their parents or outright Parental Betrayal, if you follow the line of thought that the Tams deliberately gave River over to the Academy.
Alternatively the Tams could have simply been in denial - after all River was in a government school how could anything be wrong?
Frasier: It's mentioned that two of the reasons for both Frasier's extreme clinginess towards his brother and friends and his love-life-destroying fear of rejection (apart from the fact that his first wife, his fiancee, and his second wife all left him), are a) his mother's tragic death from cancer, and b) his distant relationship with his father, which was exacerbated by said death.
The Fresh Prince of Bel-Air: Will Smith himself, who was raised by his single mother in Philly until he was a teenager as his father left them when he was only a small child, dedicating himself full-time to his job as a cross-country truck driver. Will wondered for years of his father's whereabouts, and it was in part because of the lack of a father figure that it eventually became necessary for him to move to Bel-Air with his Uncle Phil and Aunt Vivian, who took him in on his mother's request. Eventually Will's dad, Lou, inexplicably shows up at school hoping to meet his son, and the two attempt to bond despite Uncle Phil's heated objections, fearing lingering disloyalty on Lou's part. Lou tries to explain that he "felt trapped and scared", and was "not ready", and Will eagerly accepts the chance to travel with him to the anger of Phil, but he eventually comes around because he knows what this means to Will. Lou however again bails on his son, saying a "big job" is up and can't afford space for Will. Devastated, Will cuts all ties with his father, and tearfully accepts Uncle Phil as his true father.
Friday Night Lights: Has several cases of this, the most glaringly obvious being the Riggins' parents—their father lives in another city, and their mother is mentioned all of twice (and never seen.) The Colletes also have an absent father, and their mother shows up rarely and usually has no visible means of income. Becky Sproles' father has another family in Seattle. Vince Howard's father has been in prison most of his life, and his mother is a drug addict. Matt Saracen's dad is a lifelong military man, and never shown to be close to or affectionate to his son even when he's home. Matt is "cared for" by his grandmother, but given her mental and physical decline it's actually him that takes care of her.
Friends: Phoebe's father walked out on his family when Phoebe was a baby, her step father ended up in jail and her mother killed herself when Phoebe was 14 years old. Later she found her biological mother, as well as her father.
Fonzie's father had left the family when he was very young. Several episodes are built around his surrogate family (the Cunninghams) helping Fonzie try to come to terms with his father's absence. In a Christmas episode aired in 1978, Fonzie finally gets some answers after a letter is hand-delivered to him by a sailor (the letter explains that his father had joined the Navy, and that he didn't have the courage to tell him face-to-face).
At some point in Fonzie's childhood, several years after the father had left, Fonzie's mother also leaves her son behind. Fonzie goes to live with his Grandma Nussbaum, which he does until he joins a gang — the Demons and the Falcons — and is involved in minor criminal activity in both. (This is all part of the Back Story, and continues until he befriends Richie and eventually becomes a surrogate member of the Cunningham family.) In one of the later episodes, Fonzie attempts to meet with his mother, which he does ... unknowingly.
Haven: After Duke Crocker's father died, his mother couldn't take it anymore and left, forcing him to turn to crime to survive. Years later, he randomly ran into her, but she didn't even recognize him.
Nikki's dad not only walked out on her but was also abusive.
Elle's mother is never seen and Sylar kills her (abusive) father.
The Petrellis' mom: evil. Dad: committed suicide.
Actually, the father didn't commit suicide, he was paralyzed by his wife in retribution for attempting to kill her son. And the father was also extraordinarily evil.
Sylar's bio-mom was murdered in front of him by his bio-dad when he was five, adopted father walked out on him at ten, and he became an (semi-accidental) Self-Made Orphan when his adopted mom attacked him with a pair of scissors.No wonder he snapped.
Jerome's mother is implied to be very distant and never around, while his father went to jail when he was a little kid, so long ago that his little sister Poppy doesn't even remember. In season 2, an entire subplot focused on them reuniting and reconnecting.
Eddie has a similar situation, with his father, Mr. Sweet, having left when he was young. He even sent letters that never reached him, being addressed to "Eric Sweet, England." When the audience finds out about their relationship, they also find out just how hurt and bitter Eddie feels about the whole situation. Like Jerome above, he did eventually bond with Mr. Sweet.
KT's parents are implied to have died like Nina's, and she was raised by her Grandfather. However, said Grandfather eventually died, and she was sent to England basically as an orphan.
Then there are the parents that are just never mentioned, specifically Fabian's and Willow's, leading to a lot of Fanon about their parents being neglectful at best, or gone/abusive at worst.
Hustle: Emma and Sean had this with their father who had abandoned them when they were 5 and 3. This led them to becoming con artists. They even pull a con on their own father, who doesn't recognize them.
Carly and Spencer's father is in the military, whilst their mother is either dead, locked up in a mental hospital, jail or has completely abandoned them, having never been mentioned on the show once. The whereabouts of Sam's and Freddie's fathers is unknown, and Sam's mother is a depressed lump who rarely gets up before noon.
Sam's father's abandonment is finally addressed in iParty With Victorious:
Sam: Yeah, and my dad told my mom he was coming back.
Wataru, the eponymous character, never knew his father and lives alone in his house after being put there by his mother when he was a child. Later, he learns exactly why: his father Otoya died after fighting the Fangire King alongside a time-traveling Wataru in order to protect his friends and the woman he loved. His mother Maya was the Fangire Queen but, stripped of her powers, became an easy target for any Fangire looking to make a name for himself, and she left Wataru in order to protect him - which hurt her just as much as it hurt him. He also learns that his childhood best friend Taiga is actually his half-brother, but that's another trope entirely.
Masked Rider (one of the franchise's American adaptations): Don't think Power Rangers is the only series in the world of American Toku to have this as a rule. Dex, the Masked Rider, has a grandfather (King Lexian) and an uncle (usurper Count Dregon, the Big Bad.) We don't meet or hear of Grandma. His parents, though, were mentioned to have died when he was young. (Like Power Rangers RPM, the ruination of the world pre-series makes "they all got dead thanks to the bad guys" a logical assumption, but it's never made clear - and also like RPM, you wouldn't think the parents' deaths would be mentioned but not the death of Lexian's wife if it happened.)
Kamen Rider Dragon Knight: Kit has a dad but no sign of mom. Even then, his dad had gone missing pre-season and he was placed in foster care; at one point Kit states that he assumed his dad had just walked out on him.
Kung Fu: The Legend Continues: Peter Caine has a continuing case of this. His mother died when he was young, he was separated from his father when he was twelve—believing that he, too, had died—and after he was reunited with his father as an adult, the elder Caine left again repeatedly. To make matters worse, Peter's adoptive father left for personal reasons at the end of the second season and never returned (sadly, due to the death of the actor). Unsurprisingly, Peter has issues.
What Nancy, the bratty orphan who Nels and Harriet Olesen adopt, claims her mother did to her, all to gain sympathy from her new family and friends. (In truth, Nancy's mother suffered from pre-enclampsia and died while giving birth to her; when officials are unable to track down her biological father, Nancy is made a ward of the court and is moved around from orphanage to orphanage.) Charles Ingalls is able to uncover the truth after he makes a casual remark to the director of the last orphanage where Nancy was staying.
Several episodes revolved around parents leaving the family for various reasons, with the Ingalls or other main characters helping the involved child cope with their loss(es). However, at least two main characters had direct involvement:
Albert Quinn (Matthew Laboreteaux), whose drunken father leaves the 10-year-old boy on the streets of Winoka at the start of the 1978-1979 season; Albert is eventually adopted by the Ingalls family. (Several times, Albert's biological father, John, attempts to regain custody, but these efforts fail.)
Not one of the main characters has a complete set of parents - Morgana and Gwen's fathers are both dead. Neither of them has even mentioned their mother, so it can be assumed that they, too, are deceased. Arthur's mother is dead (and his father tends to treat him very coldly as a result). Merlin never knew his father, until The Last Dragonlord, in which it was revealed that he was forced to leave Hunith before he even knew she was pregnant. He is killed shortly after they are reunited. Strangely enough, though, prior to this Merlin seemed to be daddy-issues free.
Morgana views her father Uther's refusal to acknowledge her as this. Whether it should be viewed as this is up for debate as, despite not telling her, he spends a considerable amount of time with her, makes no secret that he considers her a daughter, listens to her advice, and once skipped a council meeting to go riding with her.
Monk: Adrian Monk's father left the family in 1972 while attempting to get them Chinese Food. It is later revealed that the cataclyst was a Chinese fortune cookie stating that he should "be his own man", although it is implied that the frustrations involving his family also contributed greatly as well.
Night and Day: Plenty to go around. Steph McKenzie left her son Josh Alexander in a church doorway as a baby; Danny Dexter abandoned son Dennis Doyle and his mum Roxanne when he was a baby; Django Doyle was so eaten up by his father Charlie's abandonment of him as a child that he arrived in town with the intention of killing him.
Once Upon a Time:Damn near everyone has issues about this. Special mention goes to Emma Swan and Rumplestiltskin who were both the abandoning parent and the abandoned child. Though Emma didn't abandon her son per se, she just gave him up for adoption. She still feels somewhat guilty for it.
Not to mention Killian "Hook" Jones, whose father sold him into servitude as payment for buying a rowboat to escape the law.
Regina is perhaps the only character who doesn't have these issues, and she probably would have been better off if her mother had abandoned her. Everyone else would have too.
Only Fools and Horses: The Trotters' mother Joan died when they were young, while their Jerk Ass father Reg abandoned them. They were not happy when he returned in "Thicker than Water". Del frequently speaks of his mother with great fondness.
Party of Five: The one, the only. In the pilot episode, we learn the parents were killed by a drunk driver six months prior.
Parents often go unseen, though Rangers are seldom seen in the sort of situations that make one wonder "What did Mom say when they got back from fighting the villains?" Villains conveniently attack after school but before dinner most of the time. However, in the Mystic Force season, the Rangers have been shown to pull the occasional all-nighter at Rootcore, making one wonder how they explained it. And then, there was the story in which Vida became a vampire, which took place over the course of several days... did Dad notice his daughter's fangs and aversion to sunlight? Exceptions tend to be the times one parent of one Ranger is a main character — and when this happens, count on the other parent to be curiously absent and never referred to.
Dana and Ryan of Lightspeed Rescue are the chief's daughter and son. Mom is actually mentioned once and it sounds like she's dead (old friend of Captain Mitchell said Dana reminded him of her mom, and that she'd be proud if she could see Dana now.) but that one scene is the only mention of her. (What's funny is, in Rescue Sentai GoGoFive, the Missing Mom of all five Rangers - they were a Sibling Team but there was no Sixth Ranger - turns out to be in a coma near the end, and wakes up. Finding out she's alive gives them more Heroic Resolve and they go kick butt. Power Rangers, the younger-skewing Never Say "Die" series, has her established as dead, leaves her that way, and Dana and Ryan find more than enough reason to keep fighting in the fact that Queen Bansheera unleashing every demon from the Shadow World upon the mortal realm would be bad.)
Wes of Time Force has a dad but no mention of a mom ever.
Averted for half the Rangers of Ninja Storm, whose parents may be gone but their presence is still felt: Brothers Blake and Hunter are effectively orphans and they meet the spirits of their parents briefly at the end of a multiparter.note Well, they're adoptive parents, but let's not get technical. They have a current father figure, too, in their ninja master, but he was one of many ninjas captured by the villains. As for Cam, he's one of the ones who has a dad but no mom, but this is explained as her having passed away a while ago; her husband and son still miss her and her relationships with them still affect the plot, especially when Cam goes back in time and winds up getting his Ranger powers from her.
Trent's situation in Dino Thunder (dad, no mom) is justified by adoption.
Mystic Force: We actually get a two-parent family! In fact we get a four-parent family, two biological and two adopted, once all the connections are revealed. However, we manage to get the usual situation also. Clare was raised by her aunt, Udonna, because her mother (Udonna's sister) died in the Great Offscreen War pre-series. No mention of her dad; apparently he wasn't in the picture.
Justified in Operation Overdrive: Mack has a father, but his mother is absent. You don't question it at first because that's how the show rolls, but later, it is revealed that Mack's dad is a Truly Single Parent: Mack has no mother, because he is an android that his father built because he was too wrapped up in his work to find the right woman.
In RPM, the Red Ranger's dad is a major character. No sign of Mom, though since it takes place After the End, it could be she went the way of the majority of humanity. However, that's never said - unlike his brother, whose death in battle we saw. We don't get that one line that clearly puts her in the past tense while maintaining Never Say "Die" (see Dana and Ryan Mitchell above.)
In Samurai, Skull sends his son Spike to live with his best friend Bulk, apparently so Bulk can mentor him and teach him something-or-other. What's odd is that Spike's mom is never mentioned, even though Word of God says it's Kimberly, Skull's longtime crush and the original Pink Ranger!
Villain single parents are also common.
Master Vile is the father of Rita and Rito, but no mother.
Divatox is Elgar's aunt. General Havoc, Divatox's bro, may be his father, but no mother. We also meet Divatox's mom, but the absence of a dad is explained: she tossed him into the Pit of Eternal Sorrow and the source of the screaming we heard the entire time it was open was apparently him.
Scorpius is the father of Trakeena, but no mother.
Bansheera is the mother of Impus/Olympius, but no father.
Ransik is the father of Nadira, but — you guessed it — no mother. (The same season has a Ranger whose dad is a main character, but whose mom is never mentioned.)
Lothor is the uncle of Marah and Kapri. Their parents are only mentioned in passing, but they evidently do exist.
Necrolai is Leelee's mom. Dad exists, but she had him turned into a worm at some point.
After the fall of Prince Vekar and Prince Vrak in Megaforce, Emperor Mavro comes in person to take revenge. No Empress do we ever hear from.
It's also very much the norm in other American Toku series, even those that aren't Saban's, but you'll have to look alphabetically. Really, by this point, it's a true shocker when you do get the slightest mention of the parent that isn't the one important to the show.
Punky Brewster: Punky was abandoned by her mother; as to why was never disclosed. The subject of Punky wanting to reunite with her mom came up a few times during the first couple of seasons (and once in the animated version).
Pushing Daisies: One of the main themes of this show is the effect that suffering this trope has had on the two leads. Both of them lost a parent when they were children (on the same day, in factnote This was actually Ned's fault, even though he didn't realize it at that time.). Chuck was raised by her aunts after that although one of her aunts may be her mother, while Ned's Jerkass father abandoned him at boarding school.
Quantico: Shlby Wyatt's parents, long believed to have died on 9/11, actually ended up in hiding, as a result of finding out that some shady contacts that they had made in Afghanistan were connected to the terrorist attacks.
Quantum Leap: Al's mother abandoned him and his younger, mentally handicapped, sister when they were young. Then their father put them in an orphanage, so he could travel for work. The father later died, and Al left the orphanage once he was an adult. He went back later to retrieve his sister, Trudy, but she had died from pneumonia.
Revolution: Charlie and Danny's biological mother died sometime after the blackout and their father dies in the pilot episode. Their stepmother Maggie lives, only to die in episode 4. However, their birth mother is revealed to be still alive, and in Monroe's custody in episode 2. She does get free in episode 10, but then she blatantly shows that she favours Danny over Charlie to an unhealthy degree. Sure, Danny's death in episode 11 didn't help matters, but slapping Charlie because she tried to call her out on her abandonment in episode 12, as well as leaving Charlie and fully intending to die sends the message that Charlie is better off without her in episode 13.
Sabrina the Teenage Witch: The titular character is raised by her aunts. Her dad the warlock lives in the magical Other Realm, and only shows up a few times to visit. Her mom is a mortal, which means she and Sabrina can't see each other or Mom will turn into a ball of wax. Mom is allowed to come to Sabrina's wedding in the series finale because Hilda allows the Witches Council to turn her into a candle
The Sarah Jane Adventures: Maria's parents are divorced but Chrissie appears so often that this trope isn't in play for her. However both the other kids have it: Clyde's parents — who are divorced — are never seen (he lives with his mother apparently); Luke has no father, he's an artificially-grown human but he was adopted by Sarah Jane. Series 2 introduced Rani Chandra, the only kid of the group to have her parents still together. We get to meet Clyde's parents finally, too, and Clyde's feelings on his father running off are prominent when we do.
The Secret Circle: Several of the main characters have a parent that is dead or that has not been mentioned. Cassie, Jake and Nick have lost both of their parents. This turns out to have been deliberately engineered by Cassie's father, actually alive, so that he could manipulate them better by offering them a connection to their dead parents or acting in a Parental Substitute role.
The Secret Life of the American Teenager: Gives us Ricky's parents. His dad had drug problems and sexually abused him. His mom had drug and alcohol problems and is implied to be a prostitute. Needless to say, they lost custody of him a long time ago and both ended up in prison. Though his dad got out briefly before getting busted for drugs again and his mom gets out of jail in season three and they eventually mend their relationship. However, Ricky has very loving and supportive foster parents and he considers them his "real" parents.
Tess's father left her at an orphanage from hell. His abandonment has an obvious affect on her later, once she really remembers it. (As her father ends up being Lionel Luthor, she probably would've preferred being kept in the dark about everything.)
Subverted Trope in this WB/CW television series about Superman's early years, where his foster parents are aware of his alien origin and supernatural abilities since birth and remain supportive of him.
Stargate SG-1: Daniel Jackson lost his parents to an accident (involving heavy stones while setting up a museum exhibit) when he was a kid. This is revealed when the team is trapped in an alien Lotus-Eater Machine which makes him relive this memory over and over. He was Not Amused to say the least. His granddad was too busy as an Adventurer Archaeologist to take him in so he went into foster care.
Most of the main cast seems to be missing a parent. Sam Carter's mother died in an accident while Sam was a teenager. Vala's father dropped by occasionally, but she was raised by her mother. (When asked if she'd got anything from him, she replied, "Some minor food allergies.") Cassandra lost both parents in an engineered plague, and was adopted by Dr. Frasier, who would die only a couple years later when Cassie was barely out of High School. Teal'c was forced to be a Disappeared Dad to Rya'c for awhile, because he was afraid the System Lords would use his family against him. By the time the series starts, both of his parents are dead. His father was killed by Cronus for failing, his mother was killed by a rival. Rya'c and his mother Drey'auc didn't take it well. Jack O'Neill's parents are probably dead, and Jonas Quinn doesn't mentions his. Only Cam Mitchell has both parents definitely living.
Starsky & Hutch: Starsky's father was murdered when he was young. His mother is still alive, but it is implied he was sent to California without her.
Data. His "parents" shut him off, and when he next woke up, he was the only survivor of the whole colony.
Also, Tasha Yar, abandoned by her Parents at the age of five.
Step by Step: The reason why Frank Lambert is single and left to raise three children alone. Except for the series' pilot and scattered mentions in early first-season episodes, the Lambert children's mother/Frank's ex-wife is never heard from, leaving Carol (whom Frank marries in the pilot) to fill the void.
Strangers with Candy: Jerri Blank was traded away by her birth mother for a pitcher of beer. She herself would later trade her baby son for a guitar.
Street Justice: Main character Grady lost his parents when he was 9 years old; they were Canadian missionaries to Vietnam who were killed during a raid by Viet Cong soldiers at the village where they were staying.
The Suite Life of Zack and Cody: London had a father who she never saw, any time she did see him he was hidden behind his bodyguards. He was always away on buisness so her lonliness led her to buy extravagent things every time he canceled time with her.
A really jerky one here. John obviously kept Dean on a tight leash when he was younger but what happens the first time Dean goes on a hunting trip by himself? He uses it as an excuse to ditch him. While it might have been justified, Dean obviously thought he had done something wrong:
Shifter!Dean: Me? I know I'm a freak. And sooner or later, everybody's gonna leave me. Sam: What are you talkin' about? Shifter!Dean: You left. Hell, I did everything Dad asked me to, and he ditched me, too.
The angels. God's gone missing, and left them to their own devices. As a rule, they haven't taken it all that well.
That '70s Show: There's a reason why the Formans act like everyone's parents. It's because no one else's are there. Hyde's father was gone at the beginning and his mother took off a few seasons in, Jackie's father went to jail and her mother stayed away for months (it's implied this is usual for her), Donna's mother moved away, and Fez's parents are of course in his home country (so really it's more like he abandoned them). Kelso's parents are there, but they have lots of children so no real time for him.
Torchwood: Reveals that Captain Jack's father was killed when Jack was a young teenager.
VR Troopers: Finding his dad is Ryan's main motivation. His mom? No sign or mention of her.
Elena and Jeremy's parents died in a car accident a few months before the start of the series. Elena later learns that she was adopted and meets her biological parents ... both of whom end up dead by the end of Season 2.
Stefan killed his and Damon's father, while their mother had died years earlier from consumption. Turns out she came back to life as a vampire, but abandoned them, at first because she couldn't control her bloodlust around them, and later because her feelings for them had evaporated.
Bonnie's mother abandoned her when she was very young, and her father is a very uninvolved parent. Bonnie's grandmother seems to have been the main parental influence in her life.
Tyler's father and mother were both killed, each in separate episodes. Ditto for Caroline, though her mother is one of the few people in Mystic Falls to have died of natural causes.
Matt's father may or may not be dead, but he's certainly not in the picture, and his mother is prone to leaving town for months at a time, and doesn't show up at all after the first season.
Voyagers!!: Jeffrey Jones' parents died in a car accident and he was dumped on an aunt who didn't really want him. Consequently, he latched on fiercely when the time-traveling Phineas Bogg showed up in his life, having nothing in particular to leave behind.