There's no doubt that four-year-olds love to experiment with colors. Look no further than the fingernails and toenails of Gwen Stefani and Gavin Rossdale's son Kingston for the proof.

The pop star's oldest child was spotted this weekend with a bleached blond hair that was shaved on both sides. He rocked brightly-colored fingernails and toenails in a myriad of shades as he walked out of the nail salon in flip-flops so as not to disturb his freshly-painted toes.

Rocker-mom Stefani was also spotted at the salon getting a touch-up on her black nail polish before the duo met up with Kingston's little brother, Zuma, and Rossdale for a family outing to 'Yo Gabba Gabba! Live!' in Los Angeles.

Other celebrity parents who partied with 'Gabba' over the weekend in LA included Jessica Alba, Jack Black, Joel Madden and Nicole Richie.