Machine Gun Kelly is "taking some time away from Hollywood" after his breakup with Megan Fox.

The 34-year-old musician recently "left California for a while" after the demise of his on/off relationship with pregnant actress Megan, 38.

A source told Us Weekly: "Everything has been a lot lately and he's been very anxious and wants to escape the whole situation and work on himself. At the moment, he knows they are definitely over and he's been very clear with friends about that."

Meanwhile, Megan's ex-husband Brian Austin Green - with whom she shares sons Noah,12, Bodhi, 10, and eight-year-old Journey - has told Machine Gun Kelly to "grow up" after it was alleged Megan ended the relationship when she found messages to other women on his phone.

Brian told TMZ: "I didn't even know."

The 51-year-old actor - who also has Kassius, 22, with Vanessa Marcil, and Zane, two, with fiancee Sharna Burgess - then audibly sighed when told about what Megan allegedly found on MGK's phone.

He added: "How old is he? … He's in his 30s, isn't he? … But in your 30s, like, f***. Grow up. Like, she's pregnant.

Brian wants nothing but the "best" for Megan, who he was married to from 2010 to 2021.

He said: "I just want the best for her. I want the best for the baby. I want the best for our kids. That's a shame. I'm heartbroken about it because I know she's been so excited. And the kids are so excited for life and the change and all of that."

Brian stressed he doesn't know "the facts" about the couple's split, but still thinks the news is "tragic".

It was previously Megan is "done" with MGK for good.

A source told DailyMail.com: "Megan was just done with all of it. She was done with the way that he treated her.

"When she fell pregnant, he thought it meant that she would stay with him no matter what - and it is not the case.

"The most important thing in Megan's world right now is her unborn baby and she has no problem raising the child on her own.

"She's left him before, but this time seems final."