For Dave Grohl's mother, Virginia Hanlon Grohl, there was nothing but relief her son had not become a cautionary tale, as so easily could have happened.

Researching her book, From Cradle to Stage: Remarkable Stories from Mothers Who Rocked, Ms Hanlon Grohl spoke to other mothers of famous musicians.

That included the mother of Amy Winehouse, a conversation the former English and drama teacher mum admitted scared her.

Ms Hanlon Grohl joined Brisbane’s Bigsound music festival and conference to talk about her son - the frontman of Foo Fighters and former drummer of Nirvana - and the stories of other rock mothers.

There was some genuine sadness, linked to drugs and alcohol.

She told the audience at the Judith Wright Museum of Contemporary Arts how Winehouse’s mother Janis struggled in awful circumstances to help her heroin and alcohol-addicted daughter.

“The Amy Winehouse interview scared me a little bit,” Ms Hanlon Grohl said.

“The thing about her mother is that she has been through so much for so long; she has multiple sclerosis now, she walks with a cane, but she is very exuberant about life.

“She is one of the most optimistic women I have ever met in my life. She was not morose and feeling like injustices had been done.”

Ms Winehouse had told her that looking after Amy had always been hard.

“I mean from the minute that Amy was really tiny, she was out of control. They called her 'Hurricane Amy', " she said.

"She just would not do what she was told to do. Ever. And it never got better.”

Winehouse died of alcohol poisoining in 2011.

Dave Grohl, or “David” as his mother always referred to him, was always determined, Ms Hanlon Grohl said.

She divorced her husband when Dave was seven. He learnt guitar from 12, taught himself drums and left school to tour Europe with punk band Scream before joining Nirvana in 1990. He formed Foo Fighters the year after Nirvana singer-songwriter Kurt Cobain committed suicide in April 1994.

Subsequently he has toured with Queens of the Stone Age and Them Crooked Vultures and, as a member of Nirvana, was inducted into the Rock and Roll Hall of Fame in 2014.

However, Ms Hanlon Grohl said even her superstar son struggled at first.

“David could never win. He had a school band back where we lived and in the battle of the bands every year. He could never win that,” she said.

“The guys who won, well, they won’t let him forget it. But they’re not going to get any backstage passes to his shows so it worked out all right.”

A new documentary on his career - from Scream to Nirvana to Foo Fighters - was under way, Ms Hanlon Grohl confirmed, as her son’s interest in movies expanded.

“We are doing that,” she said. “Coming soon.”

Gradually the audience learnt how the mothers of Dr Dre, Maroon 5's Adam Levine, Rage Against the Machine's Tom Morello, the Beastie Boys' Mike D and Pharrell Williams coped during good times and the pits.

And she had thoughts on why some musicians were more successful than others.

“They all reflect their culture, their history. The places where they were born and grew up are significant parts of their back stories,” she said.

But she refused to consider using her English teacher skills to help Dave with his lyrics.

“That is a territory that most of the mothers agreed not to enter,” she said as the audience laughed.

“I think most of us said, ‘No, we are not going there'.”

Still, Ms Hanlon Grohl confessed some of Dave's lyrics left her cold.

“There are some I don’t understand at all,” she said.

When asked how the brothers and sisters of rock stars coped with their siblings' fame, Ms Hanlon Grohl said Dave's older sister, Lisa, shaped his earliest music influences.

“She was the one that introduced him to her musical tastes [punk rock] when she was a teenager and I was worried that she would feel left out, that her life hadn’t been quite so special,” she said.

“But she always said she would never want people to know her name. She didn’t like people coming up to her and saying: ‘Are you Dave’s sister?'

“I, on the other hand, when I see a lady at the cabbage counter at the grocery store with a Foo Fighters T-shirt, I instantly introduce myself. I can’t help myself.

"So I think it can be hard for siblings, but from my experience, most of the families [of rock stars] are strong families.”

Bigsound continues in Brisbane on Friday.