Re: "Social Butterfly" child aspiration doesn't count preexisting friends
I'm honestly not quite sure; I had a family of eight, and since they all automatically become friends when a new Sim is born, I though it would be easy. I realized pretty quickly that it wasn't that easy, though, as it didn't count preexisting friends with me either. However, the friendship meter with one of his brothers dropped below friends, and when I made them friends again, that apparently didn't count, either. I think it's either intended to not involve family, or a pretty awful bug. Did you have preexisting friends outside of your Sim's family?
Also, I don't know about the English version, but in the (sometimes rather annoying) Norwegian version, the aspiration says "become friends with 5 other children", not "be friends with 5 other children". That might be an error in translation, or it might actually be intended, but either way, it implies that you do indeed have to make five *new* friends.
(Edit for clarification: There were some pretty nonsensical sentences in there...)