Dave Grohl shocked fans last month when he announced that he had fathered a baby daughter outside of his marriage. Taking to Instagram, the Foo Fighters frontman, 55, wrote in a statement, ‘I’ve recently become the father of a new baby daughter, born outside of my marriage. I plan to be a loving and supportive parent to her.’

Dave – who already shares three daughters, Violet, 18, Harper, 15, and Ophelia, 10, with his wife of 21 years Jordyn Blum – then vowed, ‘I love my wife and my children, and I am doing everything I can to regain their trust and earn their forgiveness,’ before adding, ‘We’re grateful for your consideration toward all the children involved, as we move forward together.’

But sources tell Closer that the couple – who have both been spotted without their wedding rings in recent weeks – could be heading for divorce as pals urge Jordyn, 48, to leave her husband.

‘There’s an intervention going on with friends of his wife telling her she can’t take him back and she needs to divorce him now, and it’s got Dave in all kinds of panic,’ an insider says. ‘One minute Jordyn wants out of the marriage and the next she can’t live without him. It’s now looking that divorce is increasingly likely given how friends are rallying round Jordyn and urging her to not put up with his behaviour.’

And it could be extremely costly for the singer, who has an estimated net worth of $330million. ‘If there’s no forgiving him, it will ultimately mean he’ll be ponying half his fortune to her,’ the source continues. ‘Word is, they didn’t have a prenup. He’ll be on the hook for an enormous chunk of change, hundreds of millions given that he’s worth over $300 million, then he’ll have to pony up a small fortune with child support payments. It’s the cost of cheating.

‘Dave has never been the type of guy that obsesses over money but that doesn’t mean it won’t absolutely sicken him to suddenly lose half his bank balance, if not more. It’s not just Jordyn that’s going to be entitled to a huge share of his wealth, he’s going to have to pay out the nose to the woman he cheated on her with for the next 18 years.’

Shortly after Dave’s shock revelation about his love child, whose mother’s identity has not been publicly confirmed, it was reported that he had hired a divorce attorney beforehand. The exact date, as well as the reason for doing so, is unknown.

Our source explains, ‘Dave retained a divorce lawyer before he made his big confession, which obviously says a lot about where his head is at. He’s clearly bracing himself for the worst. He insists he wants to hang on to Jordyn, and he’s definitely pulling out all the stops to try and get her to forgive him and stick around, but he’s got to know this is going to be a very tough thing for her to get over. It’s not like they can just put it in their rearview and pretend it never happened, there’s a child involved.’

They continue, ‘To say Dave is full of regret and kicking himself right now is the understatement of the year. He feels terrible for betraying his wife and is desperate to stop this from destroying everything they’ve built together. She’s still keeping him in limbo and not giving a clear answer on whether she’s going to walk away and take him to the cleaners or give him another chance and keep their family together.

‘She’s so hurt and angry and with so many people in her life pressuring her to ditch him most people are predicting they will eventually divorce. But, at this point she hasn’t started the proceedings so there’s certainly a glimmer of hope that he could convince her to stay.’

Dave and Jordyn, who were last pictured looking happy together when they attended Wimbledon in London in July, first met in at a bar in West Hollywood in 2001 when she was working as a producer at MTV. They tied the knot in August 2003 in a ceremony held at their Los Angeles home, with celebrity guests including record producer Clive Davis and Dave’s former Nirvana bandmate Krist Novoselic.

But their relationship didn’t get off to the smoothest of starts, according to Dave. Speaking in 2007, he said, ‘When I first met my wife, we went out on a few dates and I decided that I wasn’t ready for a serious relationship, so I just stopped calling.’

However, he revealed he later had a change of heart, admitting, ‘After three months, I had a revelation and called her back. She picked up the phone and said, “Oh, I never thought I’d hear from you again.”’

Dave, who was previously married to Jennifer Leigh Youngblood from 1994 until 1997 after he admitted to infidelities, also revealed that Jordyn was ‘pretty much’ the first person he’d ever been truly honest with. ‘Now I’ve got nothing to hide. When you’re not trying to be someone else, being honest is easy,’ he admitted in 2003.

Meanwhile, Jordyn, who previously worked as model, has largely stayed out of the spotlight and has not publicly commented on the matter. Dave turned his social media comments off after posting the announcement, while their two eldest daughters, Violet and Harper, have since deleted their Instagram accounts.

While Jordyn is said to be conflicted about whether to take her husband back, our source says that Dave is doing everything he can to earn her forgiveness and isn’t backing down.

‘He’s grovelling big time and, although money is by no means the reason he wants to save his marriage, if he can’t fix this he’s going to be looking at one of the most costly cheating bills of all time if he doesn’t find some miracle,’ the insider adds.