Gwen Stefani and Gavin Rossdale's nanny, Mindy Mann, started to dress like Stefani, a source tells Us Weekly. Credit: Jason Merritt/Getty Images for Wallis Annenberg Center for the Performing Arts

Even before Gwen Stefani allegedly confronted ex-husband Gavin Rossdale about disturbing text messages and photos she discovered between him and their nanny Mindy Mann back in February, there were warning signs of things to come, a source tells Us in the latest issue of Us Weekly.

Stefani, 46, and Rossdale, 50, first hired Mann back in 2008 on the recommendation of friends. It didn’t take long, however, for Stefani to see that something was off about their new hire.

“If Gwen would eat something or do a workout or get a new handbag, Mindy would do the same thing,” the source tells Us. “Gwen thought it was weird.”

More than that, however, the source says Mann also “began to post pictures on social media dressed in a similar way to Gwen.” (The blonde-haired Australian shared a selfie back in 2013 that showed her platinum locks swept back in a black bandana, just like one of Stefani’s red-carpet looks.)

According to a source, Stefani became suspicious when photos of the Bush rocker and Mann emerged in November 2012, with Rossdale touching their nanny’s backside as they hiked with two of the couple’s three sons, Kingston and Zuma, in L.A.

But when she found naked photos Mann sent to Rossdale, she confronted her husband, who finally admitted to a three-year affair with the family help, sources tell Us. The couple announced that they were pulling the plug on their 13-year marriage in August.

Stefani’s rep could not be reached for comment, and Rossdale’s rep declined to comment.

Get more details about Rossdale’s shocking affair, Stefani’s heartbreak, and her new romance with fellow Voice coach Blake Shelton, in the new issue of Us Weekly, on stands now!

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