Kanye West reportedly had an affair with another "A-list singer" while married to Kim Kardashian.
The Sun reports that the rapper, 44, cheated on Kardashian after she gave birth to their second child, Saint, now 5.
Just weeks after West hinted at cheating on his now estranged wife, a source told the publication that his infidelity left the reality star "struggling".
The insider went on, "Kanye cheated on Kim with an A-list singer. At the time it happened, Kanye was mainly living in his bachelor pad in Hollywood because it was closer to his studio and he wasn't going to go home to Kim and newborn baby when he'd been partying late in the studio."
They added that it was a "really tough time" for the couple.
"Kim wasn't feeling herself – the breastfeeding, the extra weight, the baby in the bedroom, the early morning exercise routines and juice diets – and Kanye was out late a lot."
And the affair is said to have put a lot of stress on the reality star.
"[Kim] was struggling and thought it was all because of how she looked – it put a lot of pressure on her at a time when she was at her most vulnerable. She blamed herself and vowed to "bounce back" hotter than ever," the source claimed.
The couple famously wed on May 24, 2014, but Kardashian filed for divorce in February this year.
Neither of the pair has spoken out about what caused the breakdown of their marriage, but the rapper dropped hints on his new album Donda he was unfaithful.
On Hurricane, track five on the album, he shocked listeners with lyrics suggesting he was unfaithful after the birth of their son.
"Here I go actin' too rich / Here I go with a new chick / And I know what the truth is / Still playin' after two kids / It's a lot to digest when your life always movin'," he says.
But his ex-wife revealed on Keeping Up With The Kardashians that it wasn't "one specific thing" that led to their split.
"I think it was just a general difference of opinions on a few things that led to this decision," she said on the show.
"And like, in no way would I want someone to think that I didn't give it my all, or not really try. You know, we have four kids.
"There's nothing that I think parents would want more than to see, or even kids want more, than to see their parents together. I grew up and I lived that myself."