When Gwen Stefani's ex-husband Gavin Rossdale says their 11-year-old son Zuma is a tough kid, he's not kidding. The rocker recently revealed that the boy broke one arm and then the other in a matter of weeks.

Rossdale shares that Zuma broke his right arm after he fell off of a chair within hours of arriving to stay with him. He has split custody of his three youngest children (including 14-year-old Kingston and 6-year-old Apollo) with Stefani. For awhile they were staying with Mom and her boyfriend, country's Blake Shelton, in Oklahoma.

Late last month — six weeks after the first accident — Zuma broke his left arm falling off his bike. Initially Rossdale says the incidents were two weeks apart, but a few moments later clarifies the accidents happened six weeks apart. It all comes at the very end of a video titled What's Cooking With Gavin Rossdale? on Haute TV's YouTube channel.

"He got a gash in his leg and five stitches and I had to take him in and ... he really beat himself up," the 54-year-old says. Zuma is the third of Rossdale's four children, three with Stefani and an older daughter named Daisy from a previous relationship.

"He's so brave and he's so strong," Rossdale says, answering a question about what he considers the greatest luxury in life. "He's a really tough kid and I'd be terrified if any of the other kids had to go through what he went through, because he's by far the toughest."

Zuma's first break was mostly healed at the time of his second, but he's got a brace and some good pain medication to help him through. "Basically his right leg is the only extremity where nothing has happened," Rossdale says, smiling. "He's amazing ... I have to remind him to not lean on his broken arm."

The exact timing of the injuries isn't totally clear. While the Haute Living episode was published on July 1, it's not known when it was filmed. However, Rossdale says his son is having a rough summer, which would indicate it was recent.

While in Oklahoma, Shelton has stepped up his step-parenting game and has seemingly developed a close relationship with Stefani's children. He hugs on them on their birthdays and teaches them things he's interested in. Stefani said as much during a gushing Father's Day post to Shelton on Instagram.

Rumors of Shelton and Stefani getting married soon have been heating up for several months, but a representative for Shelton recently told Taste of Country those rumors have no merit. They did buy a house together in Los Angeles recently, however.

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