AceShowbiz -

Britney Spears is back on the scene, making her first public outing since reaching a custody agreement with ex-hubby Kevin Federline at the Generation Rescue benefit fundraiser which was held in Los Angeles on Saturday, July 19. The singer and mother of two surprised a few when she showed up at the even, hosted by actress Jenny McCarthy and her actor boyfriend Jim Carrey.

Generation Rescue is a non-profit international organization dedicated to researching autism. McCarthy has become an activist for the cause since her son Evan Joseph was diagnosed with autism back in 2005.

An attendee told People magazine Britney kept close to her assistant and didn't speak to other guests. Yet, she "looked great and seemed really happy." She also "smiled and clapped during the video about autism. She was very into the information and watched a little bit of the dancers from Dancing with the Stars, sneaking out during one of the performances."

Besides Britney, the private celebrity fundraiser also brought out some other notable celebs, including newlywed Charlie Sheen and his wife Brooke Mueller, Robert Rodriguez and Rose McGowan who were very cozy during the event.

Last week Britney and K-Fed reached a custody agreement in their on going divorce battle. The judge ruled that K-Fed will get sole custody of young sons; Sean Preston and Jayden James, whereas Britney gets three visits a week from the boys including two overnights.

Aside from her personal life, Britney currently is working on her new album.