Sandra Bullock brought her son Louis out to a pal's birthday party in LA on Sunday. It was the latest outing for the mother-son duo that has been hanging out on the West Coast following a busy Summer of jetting around the world. They kicked things off in NYC, where Sandra wrapped up work on Extremely Loud and Incredibly Close. That movie, in which Sandra stars opposite Tom Hanks, will be out in limited release here in the US on Dec. 25. They were then off to London so Sandra could shoot Gravity with George Clooney. Now that she's in California, Sandra's been spending lots of time with one of her former leading men Ryan Reynolds. Ryan and Sandra get together frequently, went on a trip to Wyoming with Louis, and will also share the screen in the future with their project Most Wanted.