We had an experience like this with DS. At the time I didn't know it was a big deal. When he was 4 or 5 we went to a store to get a stuffed animal. He deliberated heavily between a monkey and a cat. The cat was actually exactly like a cat he had had since an infant. In the end he chose the cat. Two years later I found him in tears sobbing in his room. Reason - he felt sorry for the monkey who did not end up with a home because he chose the cat!
This is very scary to me when I think about it because he carries such intense feelings for things I wouldn't anticipate. It makes me wonder what he carries around about people and more intense situations.