In the tennis episode where Homer is all ready for the tournament when he is standing on the stairs you can see a picture of a young Marge next to a baby picture of Bart. When there is a close up of Homer look to behind some of his head. You can see a family picture where the picture of Marge used to be. Then when Marge is leaving saying shes sorry look at the picture again. It is another picture of a young Marge.