The Simpson family is a family of fictional characters featured in the animated television series The Simpsons. The Simpsons are a nuclear family consisting of the married couple Homer and Marge and their three children Bart, Lisa and Maggie. They live at 742 Evergreen Terrace in the fictional town of Springfield, U.S. and they were created by cartoonist Matt Groening who conceived the idea while waiting in the lobby of James L. Brooks's office. He named the characters after his own family members, substituting "Bart" for his own name. The family debuted April 19, 1987 in the The Tracey Ullman Show show short "Good Night" and were later spun off into their own series which debuted on December 17, 1989.

Alongside the five main family members, there are a number of other major and minor characters in their family. The most commonly recurring characters are Homer's father Abraham Simpson; Marge's sisters Patty and Selma Bouvier; and the family's two pets, Santa's Little Helper and Snowball II. Other family members include Homer's mother Mona Simpson, Homer's "Vegas wife" Amber, Marge's mother Jacqueline Bouvier, and other minor relatives.

Peter Griffin is a fictional character and protagonist of the animated comedy series Family Guy. He is voiced by cartoonist Seth MacFarlane and first appeared on television, along with the rest of the family in the 15-minute short on December 20, 1998. Peter was created and designed by MacFarlane himself. MacFarlane was asked to pitch a pilot to the Fox Broadcasting Company based on Larry and Steve, a short made by MacFarlane which featured a middle-aged character named Larry and an intellectual dog, Steve. After the pilot was given the green light, The Griffin family appeared on the episode "Death Has a Shadow".

Peter is married to Lois Pewterschmidt and is the father of Meg, Chris and Stewie; he also has a dog named Brian. He has worked at a toy factory and at Quahog's Brewery. Despite the suburban blue-collar routine of his life, he has had a number of remarkable experiences.

Peter's voice was inspired by a janitor that MacFarlane heard at his school. His appearance was a redesign of the protagonist Larry from MacFarlane's previous animated short films, The Life of Larry and Larry & Steve. The Peter Griffin character has received generally mixed to positive reviews from critics. He has appeared in several pieces of Family Guy merchandise, including toys, t-shirts and a video game, and has made crossover appearances in other shows, including The Simpsons, South Park, American Dad and the Family Guy spin-off The Cleveland Show.

Bartholomew JoJo "Bart" Simpson is a fictional main character in the animated television series The Simpsons and part of the Simpson family. He is voiced by actress Nancy Cartwright and first appeared on television in The Tracey Ullman Show short "Good Night" on April 19, 1987. Bart was created and designed by cartoonist Matt Groening while he was waiting in the lobby of James L. Brooks' office. Groening had been called to pitch a series of shorts based on Life in Hell but instead decided to create a new set of characters. While the rest of the characters were named after Groening's family members, Bart's name was an anagram of the word brat. After appearing on The Tracey Ullman Show for three years, the Simpson family received its own series on Fox, which debuted December 17, 1989.

At ten years old, Bart is the eldest child and only son of Homer and Marge, and the brother of Lisa and Maggie. Bart's most prominent character traits are his mischievousness, rebelliousness and disrespect for authority. He has appeared in other media relating to The Simpsons, including video games, The Simpsons Movie, The Simpsons Ride, commercials, and comic books; he has also inspired an entire line of merchandise. In casting, Nancy Cartwright originally planned to audition for the role of Lisa, while Yeardley Smith tried out for Bart. Smith's voice was too high for a boy, so she was given the role of Lisa. Cartwright found that Lisa was not interesting at the time, so instead auditioned for Bart, which she thought was a better role. Hallmarks of the character include his chalkboard gags in the opening sequence; his prank calls to Moe the bartender; and his catchphrases "Eat my shorts", "¡Ay, caramba!", and "Don't have a cow, man!"

Marjorie "Marge" Simpson (née Bouvier) is a fictional main character in the American animated sitcom The Simpsons and part of the eponymous family. She is voiced by Julie Kavner and first appeared on television in The Tracey Ullman Show short "Good Night" on April 19, 1987. Marge was created and designed by cartoonist Matt Groening while he was waiting in the lobby of James L. Brooks' office. Groening had been called to pitch a series of shorts based on Life in Hell but instead decided to create a new set of characters. He named the character after his mother Margaret Groening. After appearing on The Tracey Ullman Show for three seasons, the Simpson family received their own series on Fox, which debuted December 17, 1989.

Marge is the well-meaning and extremely patient matriach of the Simpson family. With her husband Homer, she has three children: Bart, Lisa, and Maggie. Marge is the moralistic force in her family and often provides a grounding voice in the midst of her family's antics by trying to maintain order in the Simpson household. She is often portrayed as a stereotypical television mother and is often included on lists of top "TV moms". She has appeared in other media relating to The Simpsons—including video games, The Simpsons Movie, The Simpsons Ride, commercials, and comic books—and inspired an entire line of merchandise.

Stewart Gilligan "Stewie" Griffin is a character from the animated television series Family Guy. Once obsessed with world domination and matricide, Stewie (voiced by Seth MacFarlane) is the youngest child of Peter and Lois Griffin, and the brother of Chris and Meg. He also has a close friendship with the family's anthropomorphic dog, Brian.

Stewie is considered to be the show's breakout character.Wizard magazine rated him the 95th greatest villain of all time.

Stewie is a one-year old prodigy who has a very sophisticated psyche, is able to speak fluently, and is intended to have a slightly camp upper class English accent. He reaches his first birthday in the season 1 episode "Chitty Chitty Death Bang," and has not been referred to as being more than a year old since, although it is presumed that he has aged to the age of at least three, as he is seen in several episodes going to Pre-school. While highly literate and able to cite pop culture references that long predate his birth, he is also entranced by Raffi and the Teletubbies. Stewie succumbs to other weaknesses of children his age – he believes Peter has truly disappeared in a game of Peekaboo, talks to his teddy bear (Rupert) as if he were alive, is overcome with laughter when Lois blows on his stomach, and has no idea how to use a toilet. MacFarlane has stated that Stewie is meant to represent the general helplessness of an infant through the eyes of an adult. Per cartoon physics, his ability to move objects of greater weight than himself is not surprising to other characters, nor is his ability to retrieve firearms from hammerspace.