Mr. Smithers, like Homer, has aged a few years since the show began. For example, Homer was 34 in Season 1, but is now 39. He has aged 5 years. Smithers has also aged 5 years; he was 30 in Season 1 and now he is 35. Heaps of Simpsons characters have aged, like Lenny, Carl, Ned, Maude and Grandpa.