‘It’s just the shape of the island, Jim-boy,’ Kit said. ‘There aren’t any real ones. It’s only a fairy story.’

I loved the way Kit talked to him: not condescending like so many people, but as you would to a younger brother. Jimmy seemed to accept the explanation and settled down again.

‘I used to pretend I was Captain Hook – you know, the pirate from Peter Pan. The one with the parrot and the hook for a hand?’ Kit went on.

‘The one who was chasing the crocodile and could hear him coming, because it had a clock in its stomach?’

‘That’s the one.’

‘I loved that story. But I was always Peter Pan, of course.’

‘It’s no fun being the goody,’ Kit said. ‘Although Peter’s a strange one, isn’t he? I always liked him too. Who would you be, Jimmy?’

Jimmy thought for a moment and then, suddenly and very loudly, he said, ‘The parrot!’

Kit began making squawky parrot noises and flapping his elbows like wings, which Jimmy quickly copied and I joined in. Soon we were all laughing so much that Kit had to stop rowing to wipe his eyes. It was wonderful to see my brother so happy, and being included in the joke for once.

Kit took up the oars again. ‘Want a go, Molly?’

‘I don’t know how.’

He laughed. ‘You said you’d been on the Serpentine.’

‘That was a pedal boat, not a rowing boat. I’ve never rowed in my life.’

‘Then now’s the time to learn. Come here, next to me.’ He patted the bench beside him. ‘You can start with one oar first.’

I moved, keeping my weight low and trying not to make the boat rock too much. Kit showed me how to hold the oar, and the motion you needed to dip the blade into the water, pulling the handle upwards towards you, then down away from you so that it swung back through the air into the right position for the next stroke. I found it impossible at first, and several times ended up ‘catching a crab’, as he called it – missing the water entirely and nearly falling backwards into the boat. But slowly the rhythm came, and he rowed too, at my speed, counting out loud so that we coordinated our strokes and stopped going round in circles, beginning to move forward in the water. It was an exhilarating feeling.

After a few moments of this, Kit said I was ready to row on my own. He handed me his oar and moved to the small seat in the front of the boat, kneeling behind me with his arms reaching round and holding mine, moving them. ‘Pull up and towards you, remember, then down and away.’ I tried to follow his directions, but the feel of his breath on my neck and the warmth of his chest on my back were too distracting.