She hangs at the back with her boys. They are loud and swing their lunch boxes wildly around their heads, disturbing the wildlife they’re supposed to be looking out for. Lizzie can’t bring herself to tell them off. She wants them to like her, wants them to think Lenny’s mum is cool. So, instead of telling them to calm down and stop swearing, she tells them Lenny’s favourite facts. Rabbits and parrots can see behind themselves without moving their heads. Most of the dust in the school hall is dead skin. Butterflies taste with their feet. Some tumours can grow hair and teeth. The first thing a human embryo develops is its bumhole.

It must be working, because Lenny catches her eye and grins from ear to ear. He looks so like his dad when he does that that Lizzie feels sick. As if Greg is still there with them. The thought makes her shiver in her clothes.

Lenny keeps a picture of his dad inside his football-sticker book, stuck wonkily between Jermain Defoe and Étienne Capoue. Lizzie wants to rip it out and burn it, but she can’t. She’s not supposed to know it’s there.

Greg had taught their son how to tackle, how to carve a place inside him that could only be filled by a football. Their back garden at home had muddy patches where a lawn should have been. They’d stay out dribbling through a haze of late-afternoon sun as it rotated into half-light, crisp twilight, then finally bled into a black too thick to see in. They’d finally come inside, red-nosed, pink-cheeked, and make giant sandwiches stuffed with crisps and cheese, layers of ham and coleslaw.

Lizzie would tut and tell them their dinner would be ruined, but they were too lost inside their football to care. They’d eat in the living room, spitting feathers over Match of the Day. That innocuous theme tune, spewing out of the speakers. Lenny, an origami bird under his dad’s crane of an arm, identical grins turning to identical scowls as Spurs made and lost chances. Lizzie would try to lesson-plan, blocking out the noise, but it was impossible.

The group is still chanting ‘We shall come rejoicing’ when they get to the windmill and stop for a break. Luke pushes Sebastian out of the way with a ‘Run around and wear yourself out,’ then plonks himself next to Lizzie on the bench.

‘Want my apple?’ He unzips his lunch box and proffers the contents to her.

‘That’s not fair, Mr Williams. How come you and her get to have your lunch now and we don’t?’

‘First, her name is Mrs Robbins, and second, because I’m in charge. Plus, I already saw you eating your sandwich on the way here.’