Sheldon Dinkleberg is one of the major characters of The All New Fairly OddParents!. He likes to be a good person to anyone, but Mr. Turner deeply despises him.
In the future, due to the Mulligans being neighbors of the Turners now, it is unknown of what happened to the Dinklebergs, but it is implied that in order to finally get rid of Dinklebergs once and for all, Daran made a deal with Dante to bring Sheldon to the Planet of the Dads and make him their slave there. The Daran clones treat Sheldon very poorly, torturing him and making him suffer, until Tommy, Tammy and other kids rescued him and brought him back to Earth. During his time as a slave, Sheldon finally realized the deep hatred that Daran has and wants to get revenge on him. After dining over and cleaning himself up at the Mulligans' house which formerly belonged to him, as well as learning what happened to his wife, Sheldon confronts Daran one last time at a retirement home, gives him a harsh speech and punches him in the chin during a brief fight before Timmy ended it and takes Sheldon to a different retirement home to rest. Sheldon felt happy that he got revenge on Daran Turner and agrees to never mention it again. He thanks Timmy's kids for getting him out and happily retires in the Miriam Dinkleberg Retirement Castle, named in honor of his late wife.
Sheldon has gray hair and is typically seen wearing a yellow (sometimes plaid) shirt with blue jeans.