Gwen Stefani showed off her amazing post baby body as she enjoyed a day at the beach in St. Barth, French West Indies with her husband Gavin Rossdale and two young sons Kingston Rossdale and Zuma Rossdale on January 4, 2010. The bikini clad rocker showed off some six pack abs that rivaled her husband's as they walked hand in hand with Kingston in between resting in the shade with Zuma and building sandcastles.