In Us Weekly's new cover story, Gavin Rossdale's three-year affair with the family's nanny is revealed.

It was a very unhappy ending for Gwen Stefani and Gavin Rossdale. In the new issue of Us Weekly, insiders exclusively reveal that the music super couple’s 13-year marriage ended because of adultery: Rossdale’s three-year relationship with the family’s longtime nanny, Mindy Mann. (Stefani’s rep could not be reached, and Rossdale’s rep declined to comment.)

Back in February, Stefani, 46, uncovered Rossdale’s long-term affair with Mann, who cared for the couple’s three sons, Kingston, 9, Zuma, 7, and Apollo, 20 months. 

At the time, the No Doubt frontwoman discovered explicit texts between Rossdale and the nanny — including nude photos of Mann and their plans to meet up for sex — on the family’s iPad. 

“The iPad was linked to Gavin’s phone,” a family source tells Us. “One of the other nannies discovered the exchange and told Gwen.” 

Mann was soon fired, but the Bush rocker, 50, insisted to Stefani that the exchange was simply “flirtation,” one source explains. When he finally confessed to the affair months later, the “Used to Love You” singer made the decision to end their marriage. The couple announced their plans to divorce in August. 

The admission “completely devastated her,” a source tells Us. “She was mortified, livid, and embarrassed.” 

The sexual relationship lasted for more than three years — including the time period when Stefani was pregnant with Apollo. 

“This was done right under Gwen’s nose,” a source tells Us. 

For all of the details on Rossdale’s shocking affair, Stefani’s heartbreak, and how she has moved on with her Voice costar Blake Shelton blossomed, picked up the new issue of Us Weekly, on stands now! 

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