I thought I had seen this discussed here, but now I can't find the thread.
I have 11 week old b/g twins. They're starting to smile at and interact with their big sisters, but they don't really notice each other. I figure they're just such a part of each other that's always there, that maybe they don't notice or realize that the other is independent of them. I don't have anything to back that up, though. :) When did your twins start to notice each other?
Well our fraternals sleep very close and one always has her hand in her sister's face. They're 3 months and don't care for each other unless it's time to sleep. I noticed during the day they might glance at each other but other than that... they couldn't care less. I think it's because it's such the norm for them to have that "other person" there nearby that it's more exciting to look around for mommy and daddy and TeenSis. And Kitty. Our fraternals get excited when the cat strolls by.