In the three years since their marriage of nearly 13 years imploded following his alleged affair with their sons’ nanny, Gwen Stefani and Gavin Rossdale have tried to not let the nasty details of their split affect their children. “We both just want the kids to be as safe and as happy as possible,” Gavin said last year, “so that’s the only focus we have.” But that doesn’t mean they always agree on what’s best for the kids. 

Though the No Doubt frontwoman, 48, and the Bush rocker, 52, finalized their divorce two years ago, they’re still having blowout fights over how they want to raise sons Kingston, 12, Zuma, 10, and Apollo, 4. The former pair are so acrimonious, they have even turned to a mediator. “They needed professional help,” an insider tells In Touch magazine exclusively, adding that the impartial referee “has his hands full.” The pair reportedly spent an entire day in mediation on Sept. 5, and the insider says Gwen and Gavin’s problems mostly stem from his jealousy about how close his children have grown to her boyfriend of nearly three years, country singer Blake Shelton, 42. “Gavin feels replaced,” says the insider. “Even though he’s the one who cheated, he has some anger issues.” 

blake shelton and gwen stefani on the voice

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Since Gwen began dating her fellow Voice coach back in 2015, Blake has become a second father figure to the boys, going hiking and taking them on helicopter rides. “Gavin says he doesn’t like that his children are being raised as little cowboys, with all that time spent at Blake’s home in Oklahoma,” says the insider. “But it’s really about Blake.” Gavin sees the fun-loving country star as a threat, says another source: “The kids are always raving about how wonderful Blake is and all the fun activities they do. But at the end of the day, Gavin is their dad, and he wants to keep it that way!” 

gwen stefani and blake shelton with kids

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For her part, Gwen takes issue with her ex’s rock-star lifestyle. “She wants the kids to be brought up in a stable and consistent environment,” says the source, adding that Gavin, who began dating 28-year-old model Sophia Thomalla last year, wants to see the kids more often once his concert tour ends in October. “But the children had difficulty adjusting to their new lives after the divorce. Gwen has worked hard at getting them back into a routine, and she refuses to let Gavin disrupt it.” The pair are also at odds when it comes to the kids’ religious foundation, as Gwen is a devout Catholic and Gavin isn’t religious. The bottom line, says the source, is that “Gwen knows he’s a good father, but she’s concerned about the effect his wild ways may have on the kids.”

Especially because Gavin isn’t acting very mature lately. As part of their 2016 divorce agreement, the exes were supposed to split the money from the sale of their Beverly Hills house, but as of earlier this year, Gwen was still struggling to sell it. She wanted to lower the price to attract more offers, “but Gavin wouldn’t let her. He was being spiteful,” a source said at the time. He just can’t help himself. “Gavin’s jealous of her perfect life,” explains the insider. “So he likes to make things harder for her. When she’s miserable, he’s happy.”’

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