Lily has moved seamlessly from her St Trinian's country prep school for 100 horse-fancying, rara-skirted girls with names like Cecilia and Tatiana, to a London comprehensive for 1,400 black-suited Jaydens and Kayas.
I, conversely, have been on the back foot since the beginning of term, owing to a) the unfeasibly early mornings after a blissful year of lie-ins, and b) leaving it to the last minute to get her school uniform. The nice jackets had run out at M&S Marble Arch when we got there at 3pm the day before school commenced, forcing us to go to the dreaded official outfitter, whose official jacket combines the stiffness of cardboard with the type of manmade fibre that sparks fly off if you get too close.
The chummy assistant handed Lily an official ready-tied tie that fastens round the back with Velcro.
'Oh God,' I muttered. 'Don't they have real ties these days?'
'Don't want any peanutting,' cackled the assistant.
'Few incidents,' she nodded knowingly at me, miming a tie-tightening throttle. 'Not many, mind, but two or three, back in the old days.' She pulled open a drawer. 'Not as bad as these,' she added, holding up a clip-on tie for another school where even quick-release Velcro is clearly not enough.
Oh lord. This isn't Candlebury.
Since then, Lily has taken up her newfound independence with a hitherto unknown burst of self-motivation, which involves setting her alarm for 6.30am, stomping downstairs at 7.10am (at which point I rouse myself and stumble down in my dressing gown to act like the dutiful mother), standing up to eat a quick bowl of Special K Red Berries while stuffing books into her backpack, before heading out across the park to team up with pals in order to walk back across the park to catch the bus to school.
'The thing is, Lily,' I venture on day 2, 'it's not very ergonomical, this little journey of yours.'
'The way you go to school. You're walking two sides of a triangle across the park and back. If you walked straight to the bus stop you could shave 20 minutes off your journey and spend another 20 minutes in bed.'
She gives me one of her steely withering looks, picks up her door key and heads out without so much as a 'bye, Mum'.
On day 3, Lily glares up at me as I appear on the stairs. 'You don't have to get up every morning,' she says. I shudder. My mother was already down, table laid, bacon and tomatoes sizzling in the pan, when I was Lily's age.
On day 5, as I attempt to hug her unyielding little body goodbye, Lily says, 'Do we have to go through this every morning?'
Oh God. I am officially redundant.