For the first 10 years of David Campbell’s life, he had no idea Jimmy Barnes was his dad.

The music legend was just a teenager when David was born and he kept up a ruse he was a “Scottish uncle” for years before he finally made the decision to come clean.

Instead, David, now 52, was raised by his maternal grandmother – and was told Jimmy was his father when he was 10 years old.

Now, Jimmy, 70,  has opened up about the life-changing moment as he fielded questions on ABC show The Assembly.

“It was very complicated,” Jimmy told an audience member who asked him why he finally revealed the secret

“David was born… and really, at that point, I couldn’t look after myself, let alone him.

“You know, I didn’t just waltz back into David’s life when he was 10 and say, ‘Hey, I’m your dad!’.

“I was going to see David from the day he was born, but he didn’t know who I was,” the star explained, adding that David’s maternal grandmother “made a point” of ensuring his true identity remained a secret.

“And I think that was a mistake,” Jimmy reflected candidly. “And it got more complicated as I got more famous.

“And as he was growing up, the grandmother got more demanding. Eventually, my wife – who’s much wiser than me – she sort of said, ‘Look, he needs to know’. So we told him.”

Recalling the moment, Jimmy shared how the news was a “huge shock” for David.

“He was reeling for a long time, and I think music, like me, saved his life,” he shared.

Building a relationship initially proves tricky.

“We started off rocky because – let’s face it – I was 16 when David was born and it was a tough time for all of us,” Jimmy told the ABC in 2019.

“We weren’t ready to deal with ourselves, let alone having a child come along. I wasn’t capable of being a decent parent at that age and for a long time.

“But I always tried to stay close enough so he’d know who I was, so we could be friends.

“I see myself in David. I see the good side of myself in David and I watch him and I just feel so proud and he gives me hope. And I hope to be just like him when I grow up.”

On his part, David looks back and sees the value of becoming friends with his dad before he knew they were father and son.

“Building a base as friends first – because we had to – has actually made it easier to be father and son now,” he told the ABC.

Today, the pair are incredibly close – brought together by a shared love of music and humour.

“There’s no words to describe a world where he doesn’t exist in it for me,” David shared. “I would be so lost. I’d hate to think where I would be.

“I hate to think what closed-off a human I would be. Because I’m only open and, I hope, as evolved as I am now, because of him in my life.”