I think I was halfway down the escalator in Waterstones in Sauchiehall Street, Glasgow, when my heart broke.
Or maybe it wasn't until I stepped off at the bottom that I realised that it had smashed like an egg dropped on the kitchen floor  .
Either way, all I knew was that suddenly my chest was full of all this gooey, runny mush punctured by jaggy shards of feeling. And it was all Tove Jansson's fault.
Rewind a few seconds. I am descending with a vague notion I may find something in the basement to spend a birthday book token on .
As I let the escalator do its work I glance left into the children's section of the store. There, on a table sits a lovely, cuddly Moomin. Sharp ears, fat snout, plump hug of a body. And I think, idly, "Oh, that would make a good present for daughter number two."
As soon as I thought it I realised how untrue it was. Because daughter number two is not cuddling soft toys any more. She is 12, nearly 13. She spends her life on Snapchat. She is on to boyfriend number two. She does not want to be tickled any more. My little girl, I realise somewhere between halfway down the escalator and arriving at the bottom, is not a little girl any more.
Of course I knew this already really. But there is knowing and there is knowing. There is knowing something intellectually and there is knowing something in the scrambled mush of your heart. In that moment this blameless soft toy crystallised the realisation.
Parenthood, I sometimes think, is like being an amnesiac in a boxing booth. Time comes along and punches you in the face and you reel for a bit and then you get up and forget that time has punched you in the face until it comes along to do it once more. Again and again life gives you these constant reminders that your children are growing up and will soon grow away.
Earlier this year, I have just remembered, daughter number two decided to give away her collection of Sylvanian Families . These tiny animal toys she had spent so long, and so much, collecting were no longer of interest. J - declutter obsessive that she is - thought this a splendid idea. She sorted out a donor, packed them up and organised their delivery. The only person bothered about the whole process seemed to be me. My daughter's childhood was being packed up and sent away, after all. I moped around the house for a bit. Daughter number two, by contrast, had moved on. "Can I have an iPhone now?"
 I'm possibly "quoting" Douglas Coupland here.
 I don't need more as we've established in Age Concerns passim. But …
 The Darwin Monkey Family were her favourites.