William looks down at his plate, impales a chip with all four tines of his fork, ploughs it through the puddle of egg yolk and taps the end in the ketchup. It’s a cold but flavoursome mouthful that he takes his time to chew. He looks up at Evelyn. She winks, her left cheek bulging with food. Happiness always takes the edge off her table manners. Her unkindness towards Robert always takes the edge off William’s happiness.

In the two years since his dad died, Uncle Robert has been a flesh and blood link to his father. Memories of him are no longer as sharp and reliable as William would like. He remembers being thrown into the air by him and sitting on his lap, burying his face in a brown wool jumper and breathing in the rich, twiggy smell of pipe smoke. He remembers standing next to him at the newsagent’s on a Sunday morning, waiting for their quarter-pound of chocolate caramels to be poured into the bag from the wide metal scoop of the scales. He remembers him chasing Evelyn around the kitchen in a rubber gorilla mask, arms stretched out to reach her, making loud monkey noises, her screaming and laughing and surprising William at how fast she could move while making all that noise.

When he worries about forgetting, Uncle Robert’s very existence is a comfort. Because not only were Robert and his father brothers and best friends, they were also identical twins. William can understand how it’s hard for his mother to be reminded so much of his father, but it troubles him that sometimes she doesn’t even seem to like Robert. Or Howard.

After lunch, they walk left along Trumpington Street and look at the lions guarding the Fitzwilliam Museum. William notices Fitzbillies on the other side of the road as they make their way back towards the school.

‘Martin always goes there with his parents for a Chelsea bun. He says they’re world famous.’

‘I’ve got biscuits for us today,’ Evelyn says, taking his hand, ‘but next time we can do it. Oh!’ She stumbles into the open gutter, landing with one knee in the water. Her face twists in pain, and William is not fooled by the sudden smile and laugh as she gets up. She’s hurt but doesn’t want him to worry.

Back on King’s Parade, they watch a copper beech leaf scooped upright by the wind and pushed along as if it’s running. Once it falls from the kerb into the gutter, Evelyn sits on the low wall and pats the spot to her left. William sits as she reaches into her bag and pulls out a Tupperware box. She holds it up, a playful look in her eye. Through the plastic, he recognises his favourites: butter biscuits. Unexpectedly, his eyes prickle.