Tootie (voiced by Amber Wood in "The Fairy Flu" and by Grey DeLisle in the series and is portrayed as a live-action adult by Daniella Monet in A Fairly Odd Movie: Grow Up, Timmy Turner!) is Vicky's younger sister, a bespectacled girl who has an obsessive crush on Timmy, often going to the extreme of spying on and stalking him; in retaliation, Timmy placed a restraining orderon her in "Kung Timmy". Timmy does however have a soft spot for her and does nice things for her in several episodes, including loaning her his fairies for her birthday after Vicky ruins it. When Vicky isn't torturing the children she babysits, she tortures her in substitution. She is also jealous of Trixie. There is some controversy between who Timmy will end up with due to the end of "Channel Chasers", where his children have similarities of both Trixie and Tootie. She does not have friends, thanks to Vicky. In the live-action Fairly OddParents movie, A Fairly Odd Movie: Grow Up, Timmy Turner!, Tootie, played by Daniella Monet from the Nickelodeon series Victorious!, is all grown-up and her physical appearance changes from plain to gorgeous. Timmy, who's also a grown-up, finally is attracted to her and thinks of giving up his fairies (who he still has) to win her heart.
Elmer (voiced by Dee Bradley Baker) is a nerdy kid with a large boil with evil thoughts, whom he named Bob, on his face. He is second to A.J. in intelligence. Elmer is often picked on by Francis, more than Timmy or other kids.
Sanjay (voiced by Dee Bradley Baker) is a 10-year-old of Indian American descent. He speaks with a high pitched voice which is often accompanied by a strong accent. Sanjay often makes references to Indian animals throughout the series. Although considered as one of Timmy's back up friends, Sanjay has never visited Timmy's house. He often has to put up with his stepfather's military ways of life as if he were in boot camp.
Trixie Tang (voiced by Dionne Quan) is primarily Timmy's object of (unrequited) affection and also one of the wealthiest children in the city. In the episode "The Boy Who Would Be Queen," it is revealed that Trixie secretly loves male-oriented things and is a tomboy. In many episodes, Timmy is seen making wishes on how to get Trixie to fall for him; sometimes she does, but later rejects him due to her reputation. She, like Timmy and his friends, gained super powers in "Big Super Hero Wish", becoming Wonder Gal, gaining super strength, super speed, and super popularity. However, in the episode "Just the Two of Us", Timmy learns that Trixie's beauty is only skin-deep, as when he wishes he and Trixie were the only two beings in the universe (with Cosmo and Wanda still by his side), Trixie becomes psychotically obsessed with his attention towards her, much to Timmy's suffocation. When Timmy decides to end their relationship, an angry Trixie chases him through the outskirts of a minimall in her attempt to kill him using sporting and gardening equipment, including a helicopter to slice him in half with the propeller blades, since the missiles were sold separately. However, this does not affect Timmy's feelings for her in later episodes. During the Wishology second and third part Trixie fell in love with Timmy. Partially because he could wish up things for her but they also shared their first kiss.
Veronica (voiced by Grey DeLisle) is Trixie Tang's obsessive best friend, often wishing she was her. Her room is decorated with pictures, posters, and dolls of Trixie, and she frequently mangles them. She is also secretly in love with Timmy.Timmy often calls her " the crazy one. She serves as a sidegag"
Tad And Chad (voiced by Tara Strong and Grey DeLisle) are two of Timmy's wealthy, popular classmates. They often make fun of Timmy and other unpopular kids, and also frequently turn Trixie away from Timmy by embarrassing him or impressing her with their money
Molly (voiced by Grey DeLisle) is a tomboy goth who was sent to the Wishing Well with Timmy to learn how to make less wishes. She grew close to Timmy through the episode. She has a fear of snakes and hates when people touch her.
Dwight (voiced by Charlie Schlatter) is a kid who was sent to the Wishing Well along with Timmy and Molly. Dwight's worst fears are harpoons because he dreamed he was a whale, and people wanted his blubber.
Tommy and Tammy Turner are Timmy's children seen at the end of Channel Chasers. They inherit their father's godparents when they are babysat by a robot version of Vicky.