Gwen Stefani, Blake Shelton and Apollo Rossdale.Photo: Gwen Stefani Instagram

Gwen Stefani’s sonApollo Bowie Flynnturned 9!
Ina sweet tribute postdedicated to her youngest son on his birthday Tuesday, the"Hollaback Girl"singer penned a special message sharing just how much he means to her to mark the milestone.
Along with the message, she posted various photos and videos of Apollo in different stages of his life as he grew up set to her bandNo Doubt’s song “Running.”
“My world is so much bigger with u in it, happy birthday, apollo ♥️♥️ i love u so much,” wrote Stefani, 53, in the post’s caption.
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By far, the biggest picture in the collage was of her with husbandBlake Sheltonand Apollo all smiling at the camera.
In the snap, Stefani looked cheerful in a green blouse and dark-blue jacket as she posed beside Apollo, who also grinned while weaning a denim jacket with his name embroidered on it.
Wearing a black shirt and matching black hat with the word “LEGACY,” Shelton, 46, posed right behind the mother-son duo.
RELATED VIDEO:Gwen Stefani’s Sons Apollo and Zuma Look All Grown Up as They Pose withBlake Sheltonat NASCAR
The latter photo appears to have been taken last month when Stefani and Shelton took Apollo and her middle sonZuma Nesta Rock, 14, to NASCAR’s Busch Light Clash at The Coliseum in Los Angeles.
The coupleshared photos posing with the boysalongside NASCAR legendJimmie Johnsonat the event, where Johnson, 47, and his wife Chandra Janway hosted friends to watch in the Legacy Motor Club suite.
In December 2022, Shelton opened up to PEOPLE aboutbecoming a stepdadto wife Stefani’s three sons. (Stefani shares Apollo, Zuma andKingston James McGregor, 16, with ex-husbandGavin Rossdale.)
“They’ve taught me something about myself that I never knew: I’m more than just a country singer or a goofy guy,” he told PEOPLE exclusively of helping raise Kingston, Zuma and Apollo.
Gwen Stefani and Blake Shelton with her sons Kingston and Zuma.Gwen Stefani/Instagram

Shelton continued, “I’m someone they actually lean on, and that’s not a responsibility that I ever had and not something that I ever considered even being into.”
“It’s a different kind of self-worth. Maybe it’s the opposite of self-worth because you put yourself way down on the rung, and they move up ahead of you,” added the singer.
Shelton announced last yearthat he would be leavingThe Voice— a decision he said largely stemmed from a desire to spend more time with his stepsons as they grow up.
“You don’t know what your regrets are going to be until you look back one day. I feel like my regrets would be, if I stayed on this path, that I am missing out on some more important things in life — and for now, that’s our kids,” he said.
source: people.com