XD the possums are Manny's girlfriend's siblings. She thought she was a possum because she was raised by them, hence Ice Age 2 is about her identity crisis. And they've been slowly making Diego a...well, a pussy since the first movie. He was a lot meaner and smarter then xD

Personally, I'm still trying to get over the fact there's even dinosaurs in the movie when they should be dead. I know they find some that are still around, but...wtf xD