Timmy goes to school where his evil teacher Denzel Crocker is being a jerk by giving all children permanently the grade F. His only social life is filled with trustworthy friends and 5 girls practically handing themselves over to him, of course this isn't good enough for poor Timmy. His parents, whom Timmy doesn't give a living crap about anyway, never have time for him because they appear to be able to take care of whatever needs he has and converse with him daily.
Timmy had a good relationship with his older brother Ezekiel. The two spent a lot of time together, mainly playing video games together. Then, the parents actually decided to care about parenthood and said Ezekiel should get out more and made him audition the Total Drama Series as a result. It was never a good idea from the start because Ezekiel was the 1st one kicked off the 1st season because of his menatlly retarded father and his sexist views. Timmy has become such a loner that no matter how happen his godparent's wishes seemed, he could never fill that void.
Then Timmy heard Ezekiel was returning to the competition in season 3. Timmy watched the Total Drama World Tour episode 21, and saw what his brother has become, a greedy, Gollumn-like Creature that has now gone bald and completely feral. Knowing his big bro will never be the same again, he wished up Poof to fill the void of having a brother. Timmy will most likely end up being exactly like Ezekiel because his parents are moronic jackasses.
He uses his wishes irresponsibly and many of them almost cause the world to end, in which he always has to fix. Regardless, he does it over and over anyways without learning his lessons.