Turning 35 today is a very different experience for most young women, compared to their mothers. Firstly, they are still considered "young women", whereas their Baby Boomer parents had probably resigned themselves to middle age by this point. Thirty-five might be when women are told their fertility "drops off a cliff" but it's also the age at which researchers say we peak - becoming more confident and happier.
It's why we think the Duchess of Cambridge should embrace her 35th birthday. But that's not to say she shouldn't be a realist. By the middle of their fourth decade, most women have learned a few valuable life lessons - and realised what was best left in their twenties.
1. It's too late to persuade people to use your full name
Your birth certificate might say Catherine, Genevieve or Henrietta, but if everyone's been calling you Toots since nursery, trying to upgrade to your full name just looks like a desperate attempt to appear grown up. Still with the shortened version or affectionate nickname - though that doesn't mean it's OK for your spouse to call you 'the missus'.
2. You have a public alcohol limit
Quick wine after work? Sipping fizz alongside foreign dignitaries? The days of drinking without consequence are over. Keep tabs and chug water - the hangover just isn't worth it. Not to mention the gnawing feeling that you asked the Canadian ambassador whether he was on Tinder.
3. There's no such thing as a grown-up
We're all just big kids play-acting at adult life. Behind closed doors, it's tears, tantrums and toys (just the expensive digital kind these days).
4. There is a ladylike way to sit
And it's called the "slant". Legs together, ankles crossed. Knees superglued. Wear your biggest knickers, just in case the paparazzi turn out.
5. You can't get away with not flossing
The gaps between your teeth are catching up with those in your memory.
6. Eye-rolling is fun
Just the right side of bitchy, sending your eyes skywards can also be interpreted as affectionate. It's the perfect conspiratorial move - especially when spending time with the in-laws. Perfect your eye roll, but don't deploy it too often - making enemies after 35 is exhausting.
7. You know the value of older friends
Gone are the days when you surrounded yourself solely with peers. Now, you've cultivated meaningful relationships across the generations, as well as having a mentor for brutally honest guidance and plenty of eye-rolling.
8. Cheap wine is not for you
There was a time when plopping ice cubes into a vinegary white at Mahiki meant you could get it down without having to hold your nose. That time has passed and your head, as well as your tastebuds, will let you know it.
9. You buy clothes in multiples
Found that perfect dress? Suddenly, you're compelled to purchase it in every colour. Remember when that beloved pair of jeans frayed in 2003? You're not going to make that mistake again. See specifically: underwear, Uniqlo heattech, polo neck jumpers.
10. You've stopped saying sorry
Over-apologising is seen as a female trait- there are even courses dedicated to stamping it out. By 35, you're at least aware of doing out and can catch yourself before saying sorry when someone else spills your cups of tea. On the flip side, you know how to grovel when it's really needed and aren't too proud to admit when you were wrong.
11. See-through clothing isn't for you
Sheer chiffon dresses that shows your bra might have been fine in your twenties. Now they make you look like an extra in Birds of a Feather. And rather than attracting bulging-eyed, young suitors, they're catnip for sleazy uncles at weddings. Charity shop please.
12. It's OK not to know any new music
You haven't got a clue what's number one in the charts. Only last week, you caught yourself calling it the 'hit parade'. You've started buying tickets for reunion tours of those bands you listened to as a teenager - it guarantees you're the youngest in the room, after all.
13. Radio 4 is the new Radio 1
Well, if you're not listening to anything current, what's the point? Besides, you've discovered the soothing properties of Just a Minute and Gardener's Question Time. Even the Archers omnibus is starting to slip through the net.
14. You have to exercise
It now takes three trips to the gym and a pilates class every week to look like you did at your fattest during your twenties.
15. You are not welcome in Topshop
Accept it, those leopard print crop tops and cut-off denim shorts were not designed with you in mind. There's a reason the staff are whispering and looking over in your direction.
16. Cooking does not involve the microwave
Nor does "putting a pizza in the oven" count. If you're totally hopeless in the kitchen, pick one classic dish and work hard to make it edible. Your friends will thank you for it.
17. Five or even six hours sleep is not enough
Those dark circles under your eyes? They're not something any serum can solve. They're also the reason you flew off the handle when your Ocado delivery swapped Parmesan for Grana Padano. Go to bed earlier.
18. Fancy dress is for other people
You came, you saw, you were dressed as Darth Vader. You were also 22 and Facebook didn't exist.
19. You have unexpected hair
In unexpected places. Your mane might be as glossy and full as ever (the odd, rapidly tweezed, grey aside) but it's the rogue hairs sprouting on your chin and upper lip that take you by surprise when you suddenly spot them under a strong light. Mainly because they're long. How many weeks has that been growing there? Why did no one tell me?
20. You can count your friends on one hand
And you don't need all the fingers. You might have 348 Facebook and Instagram friends but when it comes to gossiping in person, it's far easier to keep the same three phone numbers on speed dial.
21. Sunglasses are a must
They hide all manner of sins - the main one being your face.
22. You can keep a plant alive
No longer the parched soil of your youth. Thanks to a windowsill full of succulents, you seem to be developing green fingers and have even put your name down on the local allotment waiting list. Only seven years until you can grow your own.
23. You can keep a child alive
Whether your own or someone else's - a niece, nephew or godchild. Feed them, water them, don't let them ride their scooter into oncoming traffic. Easy.
24. Spa days aren't relaxing
Lying on a hard bed, with a towel over your eyes, while a stranger massages cold goo into your face is not a recipe for unwinding. It's ok to be thinking about your tax return as the seaweed wrap goes on.
25. Your mum knew what she was on about
When she told you to change out of your uniform after school. Now, getting home from work is like a race to get into your pajamas and slippers, and put the kettle on. Camomile tea please.
26. Decluttering is for other people
Someone bought you Marie Kondo's book but it's somewhere under a pile of magazines in the computer room.
27. Holding onto things makes it easier to stand up
Just try to avoid saying "oof" out loud when you do it.
28. Visiting your parents doesn't have to turn you into a teenager
Breathe deeply, count to 10 and help your mum load the dishwasher.
29. You can't dance
But don't let that quell your enthusiasm. Just hold back on the twerking and try to make any accidental wrong moves look "ironic".
30. Spiders aren't the enemy
Part of being a proper faux-adult person with your own home is being able to rid it of creepy crawlies without phoning your mum. Screaming the entire time is allowed.
31. You probably should have picked the younger brother
Not really, but a harmless flirt makes stale family gatherings just about bearable. And he does have that twinkle in his eye.
32. The best way to get anything at work is to ask for it
Pay rise? Promotion? These things aren't about to fall in your lap. Polish your pitch.
33. Your duvet is everything
You've discovered the joy of 90 per cent Hungarian goose down and can never go back. After all, you do spend a third of your day in bed. See also: new pillows to help with that niggling neck pain that seems to have started.
34. You know how to accept a compliment
When someone says something nice? Say "thank you" and try to believe that it might just be true.
35. Love really does make the world go round
The carefree days of your twenties might have been good fun, but having a partner you can put the word 'life' in front of and babies, if that's your bag, is an unbeatable feeling.