Kevin Federline was partying again this weekend while Britney Spears was at the VMA's. This wasn't like his normal partying though. According to People, he threw a birthday party for his two sons, Sean Preston and Jayden James. Jayden will turn one on Wednesday and Sean will be two on Friday.

Spears's parents, Jamie and Lynne, along with about 20 other guests were at the party on Sunday at Kevin's home in San Fernando Valley. It was a Cars themed pool party with balloons, banners, and ice cream cake.

Kevin and Britney currently have 50-50 custody of the boys but he is fighting for more time.