the one where lisa's professor leaves
the other one where he comes back as a cameo but lisa doesn't see him bcos she tells marge she doesn't wanna go downstairs
When Homer tells everyone why there are no photos of Maggie growing up and that the reason was he gave up his dreams and worked at the PowerPlant was so she could achieve hers. And all the pictures of Maggie are up on his wall with the words "Do it for her".
