I'm Bart Simpson. Who the hell are you?

My kids have recently discovered The Simpsons and have watched bits and pieces of "The Simpson Movie".  Tonight, I saw Tom Hanks on TV and I said to the kids "That guy played the voice of Woody in 'Toy Story'".  Declan said "I know who that is!  It is Tom Hanks!"  I asked him how he knew Tom Hanks and he said that he plays himself in "The Simpson Movie".  :\