New Gwen Stefani W/Kingston and Zuma @ B-Day Party

Spiderwebs singer Gwen Stefani was spotted out with her two sons - Kingston, 4, and Zuma, 1 1/2 - at a birthday party near their Los Angeles home on Saturday.Gwen and the nanny took the boys to a superhero-themed party. Kingston looked super cute as Superman, while Zuma looked adorable in his pantless cowboy getup.Last weekend, Gwen and her hubby Gavin Rossdale shelled out $15,000 for Kingston's 4th birthday bash!