My granddad had a 1,500-acre hobby farm that he had built up from scratch in Western Australia, so my siblings and I spent our childhoods going there a lot. That place – and the beach – was a huge part of our lives. I would define myself as someone who had a completely idyllic childhood. Except, of course, that childhood’s complicated!

I was the middle of three children and then the second of four kids when my little sister came along, when I was 10. We all got along, and were expected to do so. We had periods of arguing, but it is a real privilege being part of a gang. I guess that is something I worry about with my kids – that there are only two of them [Minchin and his wife, Sarah, have two children, Violet, 11, and Caspar, eight]. We kids did a lot together, so we never found a reason to reject each other’s choices. I guess it is an affirmation of our relationships – why wouldn’t we want to be with each other?

We were taught we were a family, and that we owed each other our dedication, without ever using words like “love”. Even when I was at uni, aged about 18, my mother would say: “You’re not going out this weekend, you’re spending time with us.” There was no choice. I’m not quite sure why no one rebelled, really, although it was a constant battle. If you ask Mum who was the most trouble as a teenager out of Dan, me, Katie and Nel, I think she would say it was definitely me.

Mum and Dad had high expectations of us as human beings – it wasn’t just about education. It’s a fantastic way to go about parenting, and I aspire to that. Things have taken a huge change – I don’t know anyone who wouldn’t say “I love you” to their children now, but my parents’ dedication and love to us was unquestionable. There is just a language difference, not an intent difference. I’m as strict as my parents – I have high expectations, too. I’d never ask the kids to do something outside their capabilities, but I’ll encourage them not to be lazy and to try hard.

I am not sure about the Freudian analysis, but I am sure there is some second child stuff that goes on, especially if they are second to outstanding first children! I was the least capable early on, and I wasn’t the hardiest child. I was a late bloomer, but I realised that people really liked it when I played blues scales and, with the piano, I had that insatiable need to prove myself. I can’t help thinking this need for affirmation might come from not feeling hugely kickass when I was little. When I found I was at good writing poems or riffs, I just thought: “Fuck, I’ll do that, then.”

My great-grandmother Lilian was in a home from my earliest memory. She had given us her pianola, along with 500 or so rolls of music to crank through it. It was always pretty crappy, but it is a symbol of my ridiculous family’s love of music. We would gather round and have singalongs, bashing out old show tunes. It may be silly, but it was absolutely a huge part of my upbringing and who we are. I suppose it was like early karaoke. We loved it.

We Minchins have been in this area of Australia for generations – one of the first in the family started the Adelaide zoo way back when. He sounds like an incredible man, going around the world and collecting species. My grandfather with the farm – Dad’s dad – was a surgeon. My dad inherited his surgical practice. His mum was English, and she met my grandfather when he studied medicine in the UK. He was engaged to someone else at the time.

Mum’s grandfather went to the Somme in the first world war. He got a head injury and lay a whole night on the battlefield before they found him. They patched him up and then he went back on another tour, which he survived, too. He was the great-grandfather who bought the pianola. I love the intergenerational nature of instruments like that – they acquire stories and lives. It is still at my parents’ house. I can picture it now. I wonder if I’ll ever have it in my kitchen?

When I Grow Up by Tim Minchin, illustrated by Steve Antony, is published by Scholastic, £12.99. To order a copy for £11.04, go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £10, online orders only. Phone orders min. p&p of £1.99