Following earlier reports of Gwen Stefani and Gavin Rossdale separating, there are multiple sources who claimed that the reason behind their separation was because Gavin was having an affair with their children's nanny, similar to that in Ben Affleck and Jennifer Garner's case. 

However, one of the so-called insiders revealed further details, claiming that Stefani fired the nanny in an attempt save the marriage as her instincts about the secret romance pushed her to make such move..

"Gwen loaned her clothes, and was very generous with the younger woman," the source said. "The nanny was very attractive.. in the beginning, Gwen trusted her and treated her as a younger sister/ best friend."

Over time, "Gwen had suspicions that Gavin and the nanny had become romantically involved."

Reports say that after the 'The Voice' mentor confronted Rossdale and the nanny, they were shocked and reacted like as if nothing was really in between them.

"No! No! Nothing's happening! We promise!", they said. However, amidst the denials, Stefani reportedly became overwhelmed by the "constant stress and scrutiny" and ended up firing the nanny.

"Gwen absolutely fired the nanny. She wasn't going to have this going on around the kids." the source said.

Another insider also revealed that Stefani is devastated about the ending of her marriage, however the singer has been 'consolable'. "But she had no other choice. She was very suspicious that Gavin was involved with the nanny," the insider continued.

The source also claims Gavin has been denying the cheating allegations thrown at him, however, Stefani's friends have warned her about the two, saying that something was really up between them.

"Gwen thinks he cheated, and they have been sleeping in separate bedrooms for months," the source stated. "So it really didn't make sense for Gavin to move out and upset the kids."

Gwen Stefani is currently one of the talent mentors of the reality singing competition 'The Voice', which is now on its 9th season.