It’s raining heavily in her drawing, and the sky is dark and thundery and lacking her signature beaming yellow sun, but at least my eyelashes are lush and my mascara hasn’t run, and I am grinning determinedly in it. I decide it isn’t intended to represent ‘Mum’s life being so crappy it’s pouring down on her birthday’ but, ‘Positive Mum, happy whatever the weather’. And if that’s the case, my ‘everything’s fine!’ act must be working a treat, which is incredible as I still feel as if I am falling to pieces inside. The only reason I’m still sharing a bed with Andy is because I’m not sure I could get away with moving to Spencer’s old room without a barrage of tricky questions from Izzy.

While she rushes off to change from PJs into school clothes – she shuns any assistance from me when it comes to getting ready – Andy presents me with a necklace of milky blue stones on a fine silver chain. ‘Thanks,’ I say, my eyes welling with tears. Don’t cry, don’t cry, don’t cry. There’s also a bottle of my favourite figgy perfume and a thoughtful collection of interesting books.

He really has gone to some effort. He is certainly honouring the occasion, which, rather than making me happy, is having the effect of triggering such a wave of grief that I can barely hold myself together. ‘Happy birthday, darling,’ he says, refilling my coffee cup like an eager elf. It’s a relief when he sets off to work and it’s just Izzy and me, setting off for school.

Although Spencer never gets it together enough to put a card in the post, he calls me at lunchtime, vowing to visit soon. Often, these promises don’t come to fruition, and I’m kind of hoping this one doesn’t. Whereas Izzy seems to be unaware of the tensions between us, I’m pretty sure our son would detect that something’s amiss.

‘What are you doing tonight?’ he asks.

‘Dad’s booked dinner,’ I reply. ‘I’m not sure where we’re going. It’s a surprise.’

‘Aw, that’s nice! Somewhere fancy, then?’

‘I have a feeling it’s not Pizza Hut.’ He chuckles, and it occurs to me as we finish the call that it’s not the restaurant booking that’s significant; it’s the fact that Andy sorted out the babysitter too. He had to ask me for her number. But the fact is, he arranged it: a first for mankind.