I didn't see my sister

Christopher was looking at a maternity picture from my pregnancy with him.  He was asking us if the picture was me - I had long blond hair and a big belly.  We said yes that's me and you are in my belly.  He seemed a little confused and we talked about if he remembered when Mikayla was in my belly and how she came out. I then told him he used to be in my belly too. He paused for a moment and then responded, "I didn't see my sister." The mind of a 3 year old - priceless.