He played with play dough.
We decided to go to the Exploratorium in San Francisco one day. It was a really great science museum, but my kids were a little young for most of the exhibits.
It is located in the Palace of fine arts, which is really beautiful. I want to return to this area, just to take better pictures.
Mark may be in his 30s and a PhD candidate, but he is still a little brother at heart. I was laughing about it for most of his visit. He tried to teach Ashlyn to burp on command. He's not worried about us teaching his cat any bad habits. He teased the kids, calling Ashlyn "Ashlina," but switching to "Ashwhina" when she was whiney. He was messing with her and she said "I don't like that." He laughed and said "that just makes me do it all the more." That line sums up my childhood relationship with my brother fairly well.