Audrey is starting to play with Eli a little these days. He is still mostly a bother to her, breaking her block towers and crawling through her toys. And she whines to me and pushes him away and says, "No! Stop it!"
But every once in a while, she crawls around with him and mimics his baby noises and they laugh together.
And I wonder what it will be like when they are a little older. If they will happily play together, or be constantly fighting... Probably a little bit of both.