In the reasonably thick file of Shit Things I Have Done, a podium finish goes to my parenting of our eldest when he started school. There, he was a representation of my mothering skills and thus had to be excellent.

The pressure. Not on me. I was sitting pretty, organising extracurriculars. But poor Jack. In prep he was advanced at maths and reading with the grade fives and scraping away at the violin to satisfy my need for reflected glory.

Everyone was exhausted, and the pursuits I pushed meant Jack took longer to find out Rubik’s Cube was his thing.

Which brings me to Prince George, who just turned 13 and will soon head off to board at Eton. Big milestones. My own failures can serve as a road map for William and Kate and any parent with a newly minted teenager.

The Waleses look to already be doing a grand job. George seems amiable and not visibly frustrated by wearing a suit whenever he leaves home. For these purposes, though, let’s leave aside royal trappings and expectations and the fact my kids didn’t grow up with lockdowns and social media other than MySpace.

Because some things never change.

Kate, let’s talk mum to mum.

Everyone wants the best for their kids. The funny thing is I no longer think the best is the best. I think good enough is enough.

Statistically speaking, your kid won’t win Olympic gold or a Nobel Prize or become PM. George complicates the maths because he actually will be king one day, but the aim is still the same.

It’s not to raise an exceptional teenager. You want one who’s great value.

One terrific holiday back in the day, we piled into a minibus at Gold Coast airport with our friends the Kerrs. Four adults, eight kids. The youngest, my godson Joseph, was maybe four. He laid down the holiday rules: “No spewing and no arseholes.”

It became a philosophy that’s lasted well outside the Coolangatta city limits. Great call for the holiday and life. No spewing is desirable. No arseholes is timeless and vital.

The best thing you can give them isn’t tennis lessons or language classes, or in George’s case, polo and Latin. Stop worrying about an ATAR score and model the basics. The easiest way to raise a kid who isn’t an arsehole is not to be one yourself.

Show them how to handle airport cancellations and booze with aplomb. How to dance, put people at ease with good manners, what to say when a friend loses someone dear.

Be the parent who doesn’t use the silent treatment, who doesn’t think the world owes them something, who says yes more than no. Be their protector, not their apologist.

Teenagers believe they’re unique free spirits but, actually, mostly they crave conformity. Whether that’s wearing the same jumper – in my day either the Ishka mohair or the Arnold Ross V-neck – or all wanting a piercing or to go to Lorne for New Year’s.

Understand that. Let them be them. If they’re not self-centred, something is wrong. Let them make terrible decisions they think prove independence and brains.

Our middle son Felix had a shoulder reco at 17. He rejected his surgeon’s rehab exercise plan: “I’ll do physio of the mind.”

Three years later, he called from a party. Had stuffed his shoulder again doing a handstand. Next reco, he embraced a less mystical rehab approach and has been cherry ripe ever since.

You have to master both staying connected and letting them be independent. Stay on it. You’re not their friend, but be forever their place to land.

Rewards for parenting a teenager don’t arrive in reports or trophies. They come when they’ve turned away enough to turn back.

In the past 24 hours, one of my adult kids has stayed the night for a roast chicken dinner, Mario Kart and to escort his nan to Specsavers.

Another texted to say she’s coming from interstate to stay in a couple of weeks. I’ve been in a five-hour text conversation with the third involving a Sauron meme and unfounded historical accusations of me being a supergrass.

No Comm Games tracksuits, sure. Who cares? No arseholes either. Enduring connection. Jackpot.

Kate Halfpenny is an author and the founder of Bad Mother Media.

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