when babies are small they do look like their daddies. I seen something about this before. Apparently it's an evolutionary thing, a throw back from cave men times. Babies looked like their daddies so that daddies wold stick around and not swan off leaving mum in the cave starving. They do change with tme though.
I know what you mean about the jealousy thing. It's so normal. I feel the same sometimes when everyone says that Oscar looks like OH's 1st boy (i get upset cos different mum = different looks surely?) But, like Wobbs said, if you look closer you see little things. Oscar has my eyes and fingers, everything else is dad.

so don't feel bad hun