1. My dad was so young when I was born.
I'm older now than my dad was in my earliest memories. I was 33 when my son was born. My dad was 28 when I was born; I can probably remember him at age 31.
I remember calling him "old". I must have been about 5 or 6. "But you're old," I said, in response to something. He'd have been about my age now. "I'm older than you," he said, if I remember rightly, "but I'm still a young man."
2. It must have been so terrifying.
I've now got this mad creature with no sense of self-preservation sprinting around bashing into things and trying to run into roads. I am entirely responsible for its wellbeing. I've managed to keep it alive and safe for 16 months; my dad managed for somewhere between 18 and 34 years, depending how you count these things.
He must have been as terrified and clueless as I am, and making it up as he went along as much as I am, but luckily I was too young and stupid to notice at the time.
3. I understand now why Dad was – and is – so amazed at everything his children do.
I watch my son do something really, objectively, not all that impressive, like making a stab at saying "crocodile" (it comes out as "dooduhdoo"), and I am immediately overwhelmed with wonder and pride. Look what you can do, I think. I remember when you were a barely animate blob. You're so strong; you run so fast; you say so many things that are sort of nearly words.
Imagine what it'll be like when he goes to school, or to university, or gets a job he loves. I think I'll never stop crying.
4. And I get why he's become more tearful as he gets older.
I've seen him tear up during The Lion King. I used to mock him for it. Recently though, I got all choked up at the bit where the whale gets beached in The Snail and the Whale (a book for pre-school children). Apparently fatherhood makes you soft.
5. I get why trips to see my grandparents meant so much.
There are few things so wonderful as seeing your child in its grandparents' arms. My mum and dad live in a different city to us, so they don't see him as often as I'd like, and the amazement when they see how much he's changed even in a few weeks is both glorious and heartbreaking.
6. And seeing your child in your grandparents' arms…
My dad was lucky enough to have a grandparent live long enough to meet me. I've been similarly blessed. Seeing my son (aged 16 weeks at the time) being held by my grandpa (aged about 4,770 weeks, I think) was overwhelming.
7. I'm filled with amazement at how Dad never seemed to be tired.
I'm always tired. They say parenthood makes you tired, but they can't get across how a year and a half of broken sleep and 5am starts sort of grinds it into your bones. Maybe it gets easier when your kids get older. But I don't think so: I remember rushing into my parents' bedroom at 7:02am (generously giving them a two-minute lie-in). I remember lying in bed crying quietly, and then getting louder until one of them would come in and see what was wrong. I think I was 22 at the time. They're just tougher than I'll ever be.
8. And how he could keep discipline kindly but strictly.
It's really difficult to look at your child's hilarious, adorable face and tell him off for stealing your glasses without laughing and undermining your own authority. It's also hard to maintain your temper at 3am when he's screaming for no good reason. Being the Stern But Fair Dad Figure is nowhere near as easy as he made it look.
9. And how he could answer the big questions, on sex and life and death…
I read too many things I was too young to understand, so I had a lot of these questions pretty early. How do you speak to a 6-year-old about whether you believe in God? And how do you tell them that you don't, without saying that they shouldn't? I have no idea how I'll do it. Dad did it seemingly effortlessly.
10. …and the small ones, about science and history and stuff.
Dad just knows everything. I've got about six months to learn all the things before my son starts asking me stuff. I get the feeling you're not allowed to say, "I have no idea, check Wikipedia."
11. It's made me realise that Becoming a Dad doesn't just happen when the baby pops out.
Yes, you're technically a father. But even the basic things, like "loving your child", don't necessarily come straightaway. I felt a lot of things when my son was born – amazement, relief, joy – but not a wash of love for this tiny, bright-purple poo-cannon. I can't speak for anyone else, but I fell in love with my son over a period of months, as he became a funny, warm little person with a gurgling laugh and a surprisingly solid headbutt.
As for the important, difficult stuff – knowing how to fix a bike, or when to call a doctor, or how to protect them from the world without swaddling them up too much – presumably that comes even later.
12. It's made me understand why Dad gave so much of his life to us.
He had a health scare a couple of years ago. We were terrified. What was weird was that he seemed to feel guilty for not avoiding it (it was sort of avoidable, but only sort of) because of the impact on my sister and me.
Then my son was born, and I realised I had to stay alive for as long as possible so I could be there for him. I smoked a cigarette on a night out recently for the first time in ages, and as well as all the other bad things that cigarettes do the next day – they make hangovers roughly 14 times worse, for a start – I felt guilty, for making it more likely that I'll break my son's heart by dying too young.
Your priorities change – I guess that's what I'm saying.
13. It's also reminded me that he hates Father's Day.
He always has. Mum and Dad are both like that about their respective Days. Crass and pointless and fake, they say; emotionally manipulative for transparent commercial reasons. I agree, actually. So I kind of hope he never reads this.