Gwen Stefani Files for Divorce From Gavin Rossdale

The rock star couple has been married for 13 years.

Gwen Stefani has filed for divorce from her husband of 13 years, Gavin Rossdale.

"While the two of us have come to the mutual decision that we will no longer be partners in marriage, we remain partners in parenthood and are committed to jointly raising our three sons in a happy and healthy environment," the couple said in a joint statement to ET. "To that end, we respectfully request privacy from the media during this time."

In documents obtained by ET, the No Doubt lead singer cited "irreconcilable differences" in her divorce petition, filed Monday, asking for joint custody of the couple's three sons: 9-year-old Kingston, 6-year-old Zuma, and 1-year-old Apollo.

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Rossdale, the lead singer of rock band Bush, filed his response at the same time and is also asking for joint custody.

The pair met when Bush and No Doubt toured together in 1995 and married in 2002.

TMZ, who first broke the news, reports that the couple has no prenup, so assets will be split 50/50 according to California property laws. Gwen, who is worth an estimated $80 million to Gavin’s estimated $35 million, reportedly checked the box on her form to deny Gavin spousal support.

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In a July 10 sit-down with ET, Stefani was coy when asked about tabloid rumors about her marriage to Rossdale and spoke lovingly about her three boys.

"It's a lot of boys," Stefani told ET at the time. "It's fun. It's a lot and they have a lot of energy -- and we have so much fun as well. It's crazy."

The 45-year-old singer opened up about her marriage and family on Ellen last November.

"Like everybody else we go through our cycles of being so happy and then being like, 'Oh my gosh.' And then being so happy it's crazy," Gwen said of her marriage to Rossdale, 49. "I mean I can't believe that I've known him as long as I have and we still have fun together.”

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Stefani also spoke with ET in early July about her fall return to The Voice alongside Adam Levine, Pharrell and Blake Shelton, who is going through a recent split after announcing his divorce from Miranda Lambert.

"I wrote the guys and I was like, 'I'm going to miss you today,'" she said during a break from filming. "It's so much fun together -- and I laugh. I think I broke my rib from laughing so hard the other day."

Rossdale joined Stefani on The Voice last fall as a mentor on Team Gwen.

"It's official!" Stefani tweeted at the time. "So excited to have @GavinRossdale on #TeamGwen."

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