Opposite them was a second photograph, the same hand with a different pebble. These ones carried much more upbeat pronouncements. LOVE, said one. HOPE, said another. KEEP GOING, said the third.

They were just words written on lumps of rock, but there was something so simplistic about them, so poignant, that Maggie felt quite moved. ‘Gosh,’ she said. ‘They’re lovely.’

‘The aim is that people take their pebbles away with them and just hold them now and then – because pebbles are so lovely to hold, aren’t they? – and remember being here: a sunny beach, on a summer’s day, feeling hopeful and positive. Like I said, almost a guarantee of happiness!’

‘Okay,’ said Maggie, even though she was more used to studying rocks rather than writing on them. The girl had charmed her with these photographs and her earnest goofy smile. It was impossible to refuse now.

‘Great! Well . . . choose your pebble and chalk, and go for it!’

Maggie picked up a large grey pebble that had a thin white stripe running around its middle like a belt. It was cold and heavy, beautifully smooth. The girl was right, it did feel lovely to hold. Then she chose a yellow piece of chalk and considered a few options.

Anything bad happening to Amelia. No. She’d never fit all of those words on the pebble, for starters.

Will left me. Another no. That was an old wound, she wouldn’t reopen it for the sake of an art project.

Dying alone surrounded by feral cats. Now she was just being silly. Come on, Maggie, for heaven’s sake, get a grip.

‘Sorry, I’m taking ages here,’ she felt obliged to say, still hovering with her chalk in hand. ‘I can’t decide what to write.’

‘It’s fine, take your time,’ the woman replied, removing the lens cap from a fancy-looking camera. ‘Sometimes just letting the first and simplest thought pop into your head is best, but there’s no rush.’

Maggie thought again of her dream, how she’d been paralysed at the top of the zip-slide, not wanting to jump. What are you so scared of? Helena had taunted her.

Maybe that summed it up: how bogged down she had become with all her no-thank-yous. How her own fear was perhaps holding her back. Being too scared to try, she chalked carefully onto the pebble, then grimaced a little as she held it out to the woman in the red dress. ‘I know this is a bit pathetic,’ she said, wanting to pre-empt any criticism.