In fiction, how you refer to your parents is a sign of your relationship with them. "Mom"/"Mum" and "Dad" (or the languages counterparts) are the most neutral and "normal" terms that most characters use. Other titles have more meaning behind them.
In some cases, switching from "Mommy"/"Mummy" and "Daddy" to "Mom"/"Mum" and "Dad" is just a matter of a younger user wanting to be seen as a "big kid." A Spoiled Brat or Daddy's Girl, especially if she is rich, will often refer to her father as "Daddy" even as most of her peers outgrow the title. In contrast, a full-grown man calling his mother "Mommy" or "Mummy" is seen as goofy or weird, signifying he is either a Momma's Boy, a Manchild, or that his mother is of the My Beloved Smother type.
"Mother" and "Father" used to be perfectly neutral terms but have become formal and old-fashioned over time. It can signify that the characters are uptight and formal, they're royalty, or that their parents are distant. Using "Sir", "M'am", and other extremely formal titles has even more weight to it then referring to them as just "Mother" and "Father". It's almost always to signify that the characters parents as abusive, aloof and unaffectionate, or are militaristic.
There's some Values Dissonance to this trope. For example, using "Mama" and "Papa" as an adult can be seen as childish in one area but perfectly normal and affectionate in another.
Compare to Calling Parents by Their Name, which is used when characters call their parents by their given name and usually signifies either lax parents or bad familial relationships. See also Japanese Sibling Terminology and Japanese Pronouns, which are just as personal for the user. Related to You Called Me "X"; It Must Be Serious and You're Not My Father.
- In Digimon Adventure 02, thirteen-year-old Mimi is known to lead a comfortable life. When being picked up from a party in one episode, she calls her father "Papa" in the original version and "Daddy" in the dub. It may have had more to do with Gratuitous English in one case, and matching lip flap in the other. In Digimon Adventure, she was ten, but called her father "Dad."
- Boruto usually calls his father Naruto "oyaji" (old man) to emphasis his feelings of neglect by his father. When he's happy with his dad, he calls him the very affectionate "tou-chan".
- Sarada does not know her father Sasuke well due to him being on a mission since she was a toddler, however she refers to him with the affectionate "Papa" (changed to "Dad" in the English dub). She also refers to her mother by "Mama".
- In Itachi's Story, Itachi usually calls Fugaku "Father" after graduating the academy at a very young age, which Itachi sees as "a distinction he drew for himself as a full-fledged ninja." When the time comes for the massacre, Itachi switches back to using "Dad," (even though he can't remember the last time he called Fugaku that), because now that he knows that he's going to be parted from his parents forever, Itachi longs for the good old days when they were a family.
- In One Piece, Vivi usually calls her father, Cobra, "Papa," but at the end of the arc, tells him "Sit down, Papa... I mean, Father." Cobra briefly remarks at how much Vivi's grown up.
- In Comic Girls, Tsubasa, a tomboyish girl who comes from a very wealthy family, addresses her parents by the very formal "Otou-sama" and "Okaa-sama" (translated as "Father" and "Mother") while at home. It's played with, though, in that this is less proof of the kind of person Tsubasa is and more of the kind of person her parents expect her to be.
- Fullmetal Alchemist
- Most of the Homunculi call the Big Bad "Father," but Greed, the rebellious offspring, is far more casual and flippant with Father, calling him "Dad" or other such terms.
- Ed usually calls Hohenheim by name due to their strained relationship (something Ed's traveling companions once call him out on), while Al, who's less judgmental of his father, still calls him "Dad." At the end of the series, after Hohenheim offers to sacrifice himself to bring Al back from the other side of the Gate, Ed angrily refuses the offer, saying "You're useless, Dad!", something that Hohenheim's happy to hear.
- Spoiled Sweet Veronica from Archie Comics refers to her father as "Daddy" even as an adult.
- Lonely Rich Kid Tim Drake usually addresses his father as "dad" or "sir", but when talking about him to others or in his inner monologue it's more often "father" or "Jack". His mom is mom or mommy regardless.
- The default fanon in Frozen fanworks is to have Anna and Elsa refer to their parents as "Mama" and "Papa" around each other but "Mother" and "Father" in public. The only time in the film they referred to them by title was when they were young children, however according to A Frozen Heart, Anna refers to her parents as such even at eighteen. It's rare for grown women to refer to their parents by such titles however fans use it to symbolize how repressed the two were growing up.
- Brave: Rebellious Princess Merida refers to her mother Elinor as either "Mum" or "Mother". She regresses to "Mummy" in the climax when she begins crying due to believing her mother is permanently a bear.
- Frozen: The sole time Elsa refers to her parents by title is she cries for help. She uses the affectionate and childish "Mama" and "Papa". This fits her young age (eight) in the scene but also shows she has a loving relationship with her parents. Over the course of her childhood she withdraws from her family due to fearing she might hurt them.
- In Shrek 2, the fully grown Prince Charming calls his mother, the Fairy Godmother, "Mummy," and it isn't lost on Fiona. As it happens, Fairy Godmother is controlling Prince Charming.
- Throughout Bambi II Bambi refers to the Great Prince as "Sir" to reflect the latter's distant and somewhat intimidating nature to him. Them fully developing a loving bond is culminated by Bambi finally calling him "Dad", an even less formal term than his "Mother" whom he had a far more relaxed and affectionate relationship with beforehand.
- The Land Before Time:
- Daddy's Girl Cera calls her father "Daddy" but her mother "Mom", showing that she's closer to her dad.
- Littlefoot refers to his mother as "Mother".
- At no point does Kylo Ren in The Force Awakens refer to Han Solo as his "father", showing just how much Ren wants to cut himself off from who he once was.
- The Santa Clause: Seven-year-old Charlie addresses his parents as "Mom" and "Dad" throughout. Scott and Laura's divorce probably made Charlie feel like he had to grow up a bit more quickly, but he still loves them.
- In Bye Bye Birdie the lead begins referring to her parents by their given names because it's the "modern thing" to do. When she freaks out about winning a contest to kiss her favorite singer, she switches to "Mother" and then "Mommy".
- In Hook, The titular character tries to get Peter Pan's son, Jack, on side by being more present and supportive than Peter himself. However, Hook doesn't really care for Jack, so despite being sore at Peter, Jack only ever addresses Hook as "Captain."
- A weird thing happens with Violet Beaureguarde of Charlie and the Chocolate Factory on film:
- In Willy Wonka & the Chocolate Factory, both of her parents are present. She addresses her mom as "mother." Judging from the fact that Mrs. Beaureguarde's only line is a First Name Ultimatum directed at Violet, we can assume that she takes a strict line with her daughter. Violet calls her father "Dad." He indulges her competitiveness, and they appear to be much closer.
- In Charlie and the Chocolate Factory, Violet's dad is nowhere to be found. Violet probably calls her mom "Mother" here because her mother is her coach. They seem to take their relationship as seriously as everything else, and to them, competition is everything else.
- In Little Annie Rooney, Annie calls her father "daddy dear" when she tries to sucker up to him while avoiding a punishment.
- Taken one step further in a flashback to Arnold Rimmer's childhood in Red Dwarf, in which his father - who is also his professor at college - admonishes Arnold for calling him "father" and insists on "Sir" or "Professor Rimmer".
- In A Song of Ice and Fire, it's part of standard etiquette among nobles to address their parents "My lord father" or "My lady mother" in public situations, but Tyrion Lannister nearly always calls his father that, because they hate each other.
- Artemis Fowl: When Artemis and his father are reunited after several years, Artemis slips into this. Fowl Sr. shakes his head, remembering that he was indeed that stern and demanding, but has now reverted to the personality his wife was attracted to (that he no longer has to deal with The Mafiya probably helps).
- In Messenger: The Legacy of Mattie J.T. Stepanek and Heartsongs, there's some discussion about the difference between being a father (merely siring a child) and being a daddy (committing to and nurturing a relationship with said child). Sometime in Mattie's early life, his parents divorced, note so he never got to know his father.
- After he accidentally causes her and her mother to get burned and leaves her to tend with her dying mother while he goes out drinking, Billie Jo in Out of the Dust stops callng her dad "Daddy". She switches to "my father" or "father". After they reconcile, she goes back to "Daddy".
- Xenofictional Literature often has animals refer to their parents as "mother" and (assuming they're present) "father" in order to emphasis their otherness:
- Most adult cats and older kittens in Warrior Cats refer to their parents by name. In the rare occasion that they do use a title, it's usually "Mother" or "Father".
- Dogs in Survivor Dogs refer to their parents are "Mother-Dog" and "Sire-Dog".
- Wolves in Firstborn call their parents "mother" and "father".
- Squirrel in A Dog's Life notes that her mother's name was "Stream", but that to her and her brother she was just "Mother".
- Bambi from Bambi calls his mom "mother", because he's an animal.
- In A Dog's Purpose, all dogs presumably only use "mother". The protagonist doesn't understand that "mom" is another term for "mother" and thinks that Ethan's mother is literally named "Mom".
- A Tale Of...:
- Snow White referred to her biological mother who died in childbirth as "Mother", showing her lack of a bond with her. She referred to her step-mother Grimhilde as the affectionate "Momma" growing up but switched to an aloof "Mother" when she became more abusive. She switched back to "Momma" after Grimhilde turned sweet again after becoming the new Slave in the Mirror, and she uses that even years later when her own children are grown.
- Subverted with Maleficent. She only calls her adopted mother "Mother" once. She's usually referred to as "Nanny". However, it's not meant in a negative manner. It's just everyone calls her "Nanny".
- In The Color Purple, Squeak was in jail for over a decade. As a result, her kids call their step-mom "Mama" but Squeak "Miss". It upsets Squeak.
- M*A*S*H: It is established that stuffy Charles calls his parents Mother and Father, while most other characters call their parents Mom and Dad. Lampshaded in one episode where Charles is trying to console Hawkeye, who just learned that his father is in the hospital and is trying to contact home for news.
Charles: While I had a father, you had a dad.
- The Fresh Prince of Bel-Air:
- Hilary calls Philip "Daddy" when she wants money;
- Carlton calls Vivian and Philip "Mom" and "Dad" respectively, except for that one time they caught him stripping, at which point and alarmed Carlton blurts out "Mommy!"
- Philip is "Daddy" to Ashley, who is Philip's baby girl and has him wrapped around her finger.
- Nicky can't be older than seven by the end of the show's run, but he's very bright and addresses Philip as "Dad."
- Will's father Lou, who walked out on Will and Vy when will was three, comes to the Banks residence to visit Will. Will is so happy to have his father back in his life that he calls him "Pop" and "Daddy-o." When Lou announces he's leaving Will again, a crestfallen Will addresses his father for the last time as "Lou."
- The intro to "What Is This Feeling?" in Wicked establishes the differences between the two main characters by how they address their parents. The spoiled Daddy's Girl Glinda refers to her parents by the cutesy-sounding "dearest, darlingest Momsie and Popsicle". On the other hand, Elphaba (who is more serious and has a distant relationship with her father) refers to her father as "my dear Father".
- Blazblue Central Fiction: When Kokonoe finally meets her mother, Nine, she addresses her with "haha-sama", "haha" being the formal word for "mother" and "-sama" being a honorific that signifies deep respect.
- Gladion from Pokémon Sun and Moon refers to his mother as both her first name and as "mother", to show their distant relationship. His sister Lillie uses "Mother" as well. Their family seems to be wealthy, so that might also be a reason for the title (ignoring the abusive mother aspect).
- As with all protagonists, Eilio/Selene from Sun and Moon refer to their mother as "Mom". In a throwaway line, they refer to their father as "father". This implies a distant relationship, made more noticeable by the fact Mom seems to have moved to Alola alone, however it's never given any further specification.
- Fire Emblem Fates, Hinata is slightly dismayed to hear his son Hisame, a very serious and mature individual, calling him "Father" when Hinata visits Hisame in the Deeprealms, since the last time Hinata visited, Hisame called him "Dad." Hisame then reminds Hinata that given the nature of the Deeprealms, it's been much longer since the last visit than Hinata realizes, and Hisame's bitter about his father not visiting that often.
- In Chrono Trigger, Marle calls her father, the king of Guardia, "Father," partly due to being royalty and partly due to having a strained relationship with him. At the end of Marle's personal quest she hears a story about her being happy to see all her favorite people gathered around her mother's deathbed. The following exchange then takes place, signifying the reconciliation between father and daughter.
Marle: So that's how it was...
King: Yes, why?
Marle: I used to call you «Daddy?»
King: You did.
Marle: I'm sorry...Daddy. I'm really sorry for doubting you.
- Discussed in Higurashi: When They Cry. As a child in the '60s, Miyo hears from her friend that it's new and fashionable to refer to your parents as "Mama" and "Papa" instead of the traditional Japanese terms. Alas, Miyo never gets the chance to call her parents this as when she returns home she learns they both were fatally wounded in a bus crash.
- In Kevin & Kell, Lindesfarne starts off calling her father "Daddy," but gradually switches to "Dad" as the strip starts allowing its characters to age, and she goes off to college. While she called her adoptive mother Angelique "Mother" in her youth, after Angelique walks away from her family, Lindesfarne eventually calls her by name, signifying that she no longer considers Angelique a mother.
- The Amazing World of Gumball:
- In a strange example, Darwin calls his adopted parents "Mr. Dad" and "Mrs. Mom". This isn't saying so much about his relationship with his parents as showing Darwin to be polite and a bit eccentric. The Origins Episode showed this came from Darwin calling Richard "Mr. Watterson", Richard asking to be called "Dad", and Darwin Comically Missing the Point.
- Billy always addresses Felicity as "mother". Partly this is because Felicity is somewhat controlling, but it's mostly because Billy is extremely formal and polite (despite being four).
- In The Cleveland Show, Cleveland periodically berates Cleveland Jr. because, among other things, he still calls Cleveland "Daddy" at fourteen years old.
- Ed, Edd n Eddy: Edd always refers to his parents as Mother and Father. They also refer to themselves this way in the sticky-notes they leave along the house.
- The titular character of Little Bill is five years old. He calls his mother "Mama," but admires and wants to emulate his father enough to call him "Dad." Little Bill's siblings, eight-year-old Bobby and ten-year-old April, call their parents "Mom" and "Dad." Everyone thinks so highly of their great-grandmother that they call her Alice the Great.
- OK K.O.! Let's Be Heroes:
- There's a boy in The Proud Family named Michael. He can't be much younger than fourteen-year-old schoolmate Penny, and he calls his father "Daddy." The problem is that his father is the school's P.E. teacher, who would rather Michael call him "Coach" in public.
- Raven from Teen Titans at first calls her mom by her name when they meet. She switches to "mother" a sentence later. This shows her detached, emotionally repressed upbringing.
- Utilised iconically in The Simpsons. Bart regularly calls his father, Homer, by first name or other more derogatory titles to display his cocky impudence (though he also calls him "Dad"). In the original shorts, Lisa did similar to show her similar bratty characterisation, though when she diverged into a more precocious, well behaved child, she started referring to him solely as "Dad". As shown in the flashback episode "Lisa's First Word", both kids referred to Homer by first name even as infants, building up to the heartwarming final scene where Maggie calls him "Daddy", though out of earshot.
- Used in Miraculous Ladybug:
- Protagonist Marinette refers to her parents as "Mama" and "Papa" in the original French despite being a teenager, hinting at their close and loving relationship; in the English dub, she uses the age-appropriate but still affectionate "Mom" and "Dad". Co-star Adrien in contrasts uses "Father" for the present but emotionally absent parent he has remaining (even using a French word for "you" one normally reserves for strangers in the original language), alternating between "Mom" and "Mother" for his Missing Mom.
- Though parents don't come up as much with other characters, Marinette's babysitting charge Manon uses "Mama" and "Mommy" for her mother and Adrien and Marinette's classmate Alix uses the age-appropriate but affectionate "Pops" when she is seen with her father. Alpha Bitch Chloe uses both "Papa" and "Daddy" depending on dub, indicating her Spoiled Brat status and his Pushover Parent nature.
- When TLC's titular Little Couple, Jennifer Arnold and Bill Klein, adopted their son Will from China, they encouraged Will to call Bill "Baba," Mandarin for "Daddy." After Bill and Jennifer adopted daughter Lily from India, the children were encouraged to simply call Bill "Daddy." This was probably done to make it easier on the kids, as Bill had become a father to children from two different cultures by this point.
- Fred Rogers consistently referred to his parents as "Mother" and "Dad," implying that while Fred and his father had a more playful relationship, mom was the disciplinarian of the household.
- Even her closest blood relatives have to address the Queen as "Your Majesty" in formal situations. Apparently official protocol dictates that when first meeting Queen Elizabeth and the Duke of Edinburgh in the morning, even her immediate family have to call them "Your Majesty" or "Your Royal Highness" on the first encounter of the day. It is believed the current monarch is more informal than that to her children and grandchildren. Apparently.