‘Look at how concave her foot is,’ she said. ‘Lovely.’

‘Good feet, old Maple,’ Jack agreed. ‘Horses can have flat feet like people. And the flatter they are, the more problems. Look at all the weight she has to carry.’

My mother straightened up. ‘Leo used to say – no feet, no horse.’

Dressed in skin-tight Sweaty Betty leggings and top, my mother looked particularly gorgeous today. Hair and make-up were always a major operation for my mother, but you could tell when she had made a special effort.

Her face lit up as a car pulled up in front of the house.

Spike.

My mother’s one-to-one yoga class with Spike. She touched her hair, examined her face in the hand mirror.

‘The highlight of my day,’ she said, and there was a time in my life when I would have cringed inside to hear my mother say that ninety minutes on a yoga mat with a man half her age was the highlight of her day.

But now I found it brought tears to my eyes.

She handed Uncle Jack the nailing hammer.

‘Careful with that,’ my mother said. ‘It’s bloody sharp.’

After I had cleaned Maple’s tack I walked down to the house, my clothes damp from the warm water I had used to clean bridle, bit and saddle. The smell of saddle soap and leather conditioner on my hands was like a memory of childhood.

I could see my mother and Spike through the window.

He was stretching her out at the end of their session, his large body bent over her neat little prone form, and he grinned with great amusement at me through the glass, as if I was interrupting something.

And as if he could have my mother if he wanted her.

I kicked off my riding boots at the door and went to the kitchen to drink tea and stay out of their way. When I came back, my mum was giving Spike an Air Mail envelope – such was her delicacy giving money to the help – and they were scheduling their next session.

Then she had to run to pick up Marlon from school and bring him back for tea.

I walked her to the door as we discussed Marlon’s stuffed itinerary of playdates, pick-up times and parties, swimming class, violin lesson and drama club. Bringing up a six-year-old was like being the PA of some multi-national CEO.

But Marlon was our great project. He was what we talked about. After a lifetime of antagonism, child care had brought us together and as I waved off Jen, I knew that she was a single parent’s greatest ally – the doting grandmother. And I would always be grateful to her.

Spike was rifling through the fridge in my parents’ large open-plan kitchen like an overfamiliar lodger.

In the distance, Uncle Jack was stabling Maple.

Spike turned to me, a can of Sapporo in his hand. ‘You don’t mind?’

It was a big can of beer. How long exactly was he planning to stay?