A couple of months ago, as Ava repeatedly poured water over a spluttering Ruby's head while they enjoyed their evening bath, some elves snuck into the house and transformed Ava's cot into a little bed, complete with cute doggy duvet set.
Her face, when she set eyes on it, sparkled. She couldn't quite believe that bed was hers and she loved it so much she repeatedly hugged it (as we tried repeatedly to get her into her pyjamas). The next two nights, she just couldn't wait to climb in and snuggle under her big new duvet – and she slept very soundly until morning.
Great! I thought we had made that transition very smoothly indeed. What a clever girl.
But now I realise it simply didn't occur to her immediately that, in the absence of 40 or so wooden bars, she was free to exit the bed, wander around upstairs for an hour or two after we had tucked her up and, during the darkest hours, essentially choose where she wished to sleep.
All this has now occurred to her.
So every evening, we put the girls to bed, kiss them, tickle their tummies, wish them sweet dreams and come downstairs for some much needed adult time and our meal. And about 10 minutes later, we'll hear it – some little noise that gives Ava away. But she's so quiet as she steals around after hours, sometimes we hear it too late. Like last week, for example, when my ears pricked up at something that sounded suspiciously like a beaker being dropped into the bathtub.
When I swung open the door, I was hit with an eye-wateringly minty aroma to accompany the sight of Ava's latest artistic creation. Using my toothbrush (not hers, mine), she had covered herself, the floor, the shower door and the side of the bath in a gloopy layer of toothpaste.
She beamed at me (presumably to show me that she had also put some of it in her mouth and had nice shiny teeth) and I tried not to to let the hysteria bubble up at the sight of one half of her hair sticking out horizontally, crispy and white... at 9pm.
Nocturnal naughtiness aside, the ad hoc nature of our sleeping arrangements have been rather revealing. Several times a week, Ava manages to sneak into our room, climb up on to the bed – avoiding all limbs – and snuggle under the covers without us even noticing. Until, that is, out for the count, she turns herself around and kicks one of us (most frequently Dan, thankfully) in the head.
So she is scooped up and gently placed back in her own room – but she's like a homing pigeon. Almost in her sleep she realises what has happened and, when we wake (hopefully by which time it is just about daylight), there she is again, snug as a bug in someone else's rug.
While the whole thing is making me tired (I mean, more tired than normal), I'll secretly admit it warms my cockles. Ava will be three in a couple of months time and, by day, she insists she is a properly big and very grown up girl. But in that vulnerable fug of sleepiness, there is something in her which still instinctively draws her to our sides. However precariously close I am to the edge of the bed, she's right there, sleeping very soundly – just as long as her body is in contact with mine.
So, as I watch my baby (who is now almost half my height and has already perfected the art of the convincing argument) grow up terrifyingly fast, I think I'll allow myself to enjoy these moments of togetherness when, in the fug of my own sleepiness, we tangle up so tight we're as close as we'll ever be again to being the same person.