In general, Lily is a very, very, very happy baby. It’s hard to believe that she’ll be six months old this week.

And though it’s not too difficult to get her to laugh, Lily thinks her brother Tommy is the funniest person in the world. She laughs at every stinking thing he does. If he just walks in the room, she starts smiling, and if he just jumps in the air she’ll start laughing. This video is just a small sample of how he can crack her up by doing the smallest things.