Gwen Stefani and her son Kingston arrive at JFK airport in New York City on July 24, 2012. Credit: FAMEFLYNET

Kingston Rossdale's feeling blue!

Always the young trendsetter, Gwen Stefani and Gavin Rossdale's 6-year-old son showed off a new blue 'do Tuesday at New York City's JFK airport.

Clad in a pirate-themed tee, red jeans and blue Venettini boat shoes, Stefani's oldest son accessorized his airport look with a smiley face arm tattoo and a hint of metallic nail polish, visible when he clasped mom Stefani's hand.

This summer is not the first time Kingston has rocked the hue. In July 2011, the stylish tot debuted a bright blue mohawk and shaved sides. Kingston and his younger brother, Zuma, 3, are no strangers to boundary-pushing kid ensembles.

Mom Stefani -- who helms her own L.A.M.B. fashion line, and teamed again with No Doubt to recently release "Settle Down," their first single in a decade -- has dressed them in everything from leggings to mini combat boots.

Stefani and her Bush front man hubby Rossdale have long encouraged their boys to be free spirits, but Stefani admits it can be tough raising fashion-forward Kingston. "Kingston's whole thing is, 'I need, I need.' He is insane right now," she told Elle magazine when her son was 3. "We're just hoping for the best and that he's not going to turn out to be a freak, but we'll see."