Although Gavin Rossdale seems to still be fighting for his marriage with Gwen Stefani amid the divorce, a new report claims that the Bush lead singer cheated.

According to Entertainment Tonight, Gavin Rossdale had an affair with the family nanny for three years while he and Gwen Stefani were still married.

Apparently, the 46-year-old "The Voice" judge found out about Gavin Rossdale's affair with Mindy Mann, who took care of the ex-couple's three sons: 9-year-old Kingston, 7-year-old Zuma, and 20-month-old Apollo.

Us Weekly reports:

"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."

A source says, "The iPad was linked to Gavin's phone. [...] One of the other nannies discovered the exchange and told Gwen."

Mindy Mann was soon fired after, but the 50-year-old British rocker claimed that he was simply "flirt[ing]" with the nanny.

To make matters worse, reports claim that the three-year affair was still going on while Gwen was pregnant with Apollo - she gave birth to their third son on February 28, 2014.

"This was done right under Gwen's nose," said a source.

As it turns out, Gavin eventually admitted to the affair a few months after. The "Used to Love You" singer then decided to end their 13-year marriage. It was in August when Gwen Stefani announced their divorce.

The confession "completely devastated her." According to a source, "She was mortified, livid, and embarrassed."

It seems as though Gwen Stefani has healed and moved on from the whole ordeal, though. Her upcoming album actually speaks for itself, Stefani called it "a breakup record."

Not only that, but she's also dating fellow "The Voice" star Blake Shelton. A rep for the country singer confirmed the rumors last week.