Blake Shelton may not be biologically related to Gwen Stefani‘s sons, but middle child Zuma is starting to bear quite the resemblance to his country star stepdad.

In through-the-years photo montage Stefani shared to celebrate Zuma’s 16th birthday on Thursday (Aug. 22), the resemblance is especially striking. The photo montage starts out with baby pictures, showing Zuma as a sweet, blue-eyed infant who looks a lot like his mom.

But as he gets older – and especially in the years after Stefani and Shelton started dating – the country influence on Zuma’s style is undeniable. He starts rocking a cowboy hat and playing guitar more often, and in one recent photo of him and Shelton, Zuma is a dead ringer for his stepdad.

“Happy sweet 16, Zuma!! We love u SO much,” Stefani writes in the caption of her post.

Even though Shelton seems to have had a big influence on Zuma’s musical style, the young boy seems to have had an interest in music long beforehand: In one photo of him strumming a guitar, he doesn’t look much older than four or five years old.

Zuma’s musical side could have easily come from his pop superstar mom or his rocker dad, Gavin Rossdale, too.

Zuma showed off his country side during his debut live performance at Shelton’s Oklahoma Ole Red location last month. He wore jeans and a cowboy hat when he stepped onstage and performed a rendition of Zach Bryan‘s “Oklahoma Smokeshow.”

Zuma is one of three children Stefani shares with her ex-husband, Bush guitarist Gavin Rossdale.

Carena Liptak is an Associate Editor and staff writer at Taste of Country. She specializes in breaking country music news, interviews and lists. In particular, she’s got a soft spot for sad songs — check out her roundup of the 50 Saddest Country Songs of All Time!