Sometime in the late 80s, Virginia Hanlon Grohl sat on the side of a stage and watched her son's band play their first headlining big-stage show. Her son Dave was in some band called Nirvana.
As the lights came up, her son hid his nerves by pounding the drums. As his mate Kurt Cobain wailed, she stood transfixed and astounded by the challenging new music and the energy of the crowd reflecting back on the young men.
It was an epiphanic moment. She realised she had just lost her son to rock 'n' roll -- and she couldn't have been happier.
Thirty years later she's releasing her own work. From Cradle To Stage is the story of 18 musical superstars' rise to fame and fortune.
But it's their mums' stories: the burdens they bore, the inspiration and support they provided.
Virginia Hanlon Grohl is on the line from Encino, her and her son's LA hometown for more than four decades.
She speaks in a comforting way where everything seems simple and is what it is. Her famous son inherited the same disarming honesty and earnestness.
She tells me that after all her years watching Dave from side stage, she wondered what were the experiences of other mothers of famous musos. A friend said, "write it" and so she did.
She sought out the mums and collected a diverse bunch: Dr Dre's mum Verna Griffin, from the battleground of Compton in the 70s and 80s; Hester Diamond, mother of Mike D, from the Beastie Boys, who is a leading intellectual in Manhattan; Miranda Lambert's mum, a private investigator who spent two years investigating former President Bill Clinton for Paula Jones; Janis Winehouse, Amy's mum, who was battling multiple sclerosis as her baby battled her own demons in the glare of public light; Dave Matthews' mum Val, who raised her children in South Africa and America and in the turmoil of both instilled a sense of social justice into her talented son who would find stardom with his eponymous band.
A teacher for 35 years, she has written the stories in a frank and evocative way.
All the mothers were self-effacing in their responses -- "I'm just a mum". But Hanlon Grohl discovered they were anything but. Like Manya Rubenstein, the mother of Rush's Geddy Lee. A Polish Jew, Manya survived Auschwitz and Bergen-Belsen while just a teen.
Her husband died while still young and she raised her family single-handedly. With so many disparate backgrounds and resources it's remarkable to see how many similarities there are in their stories.
Pivotal moments they all shared: the spark, the conversation, and the payoff.
"The spark" is the moment the mothers and the kids realise that music is their master or salvation.
Dave Grohl writes in the foreword that his moment came in 1975 with a family singalong to Carly Simon's He's So Vain in a car. He was 6. His mum did the the counterpoint harmony, which blew his mind and from that point he listened to every vocal differently.
Hearing harmony for the first time, realising the voices were creating chords. He calls it the rush of realisation.
I ask Hanlon Grohl about that day and until Dave wrote that in his foreword, she had no memory of the story. Dave has always been very close to his mum, calling her his muse.
The commonality is quite profound. All the children who became stars were branded hyperactive or ADHD and they failed at school. But put an instrument in their hands and they'd play for 12 hours.
As Hanlon Grohl writes, "They got less sleep, earned worse grades, made friends outside their neighbourhood circles. They looked less and less like the Norman Rockwell poster children we had planned on." But they got the last laugh.
The other commonality is the musician's instant affinity with the craft. Most of these superstars didn't have a lesson in their life.
Geddy Lee from Rush listened to his sister's piano lessons, which were an abject failure for her. He strode up to the piano and played it perfectly based only on what he'd heard.
Genetics? Hanlon Grohl says it's magic. Superstars are born not made. For every mother and their superstar children there came a moment of commitment, when the kids decided that they wanted to make their life in music.
That meant "the conversation", when parents and kids sat down and discussed the kids' future.
But not all parents were so supportive. Dr Dre's mother slapped him when he said he was leaving the family battling it out in the wilds of Compton to go on tour with NWA.
Geddy Lee had it even worse. Not only was his mother concerned for his safety but his teachers and school principal actively advised against it.
The 18 musicians at the heart of the book were all real talents and so "the pay-off" came soon enough with the parents in the book benefiting from the children they supported. There are stories of houses and cars and love and pride.
But with the fame and fortune came sex, drugs and the sleaze of headlines. Most of the parents kept the lines of communication open so they knew what was true. Their support was unconditional as long as there was honesty.
However, nothing can hide the pain the mothers of Amy Winehouse and Kurt Cobain. Fame chewed them up and spat them out. From Cradle To Stage is homespun and human.
It's the stories of special kids and sympathetic mums who blunder their way through normal life until they recognise the talent that makes a kid unique.
In that story we can all learn lessons about recognising our children's strengths and weaknesses.
I ask Hanlon Grohl if there's a second book in her. "I've been blessed with a special story. I've told it and now it's time to get back to being a mum."