‘Oh?’

She nods. ‘I remembered it then, as soon as Aoife said it – Cora was a bit behind, following Lily as usual, calling her. But all of Lily’s attention was on Gavin. She had her arms out, as though she wanted to hold his hand or get him to pick her up. We couldn’t hear what they were saying, but suddenly Lily’s arms dropped, and she started to cry. Gavin didn’t stay to ask what was wrong or comfort her, he just turned and walked away.’ She pauses, composing herself. ‘That’s when I realized he didn’t need to ask what was wrong – he’d caused the tears. I’d forgotten about it but as soon as Aoife said it, it was there, clear as day. Then Aoife said something about the door with the barrels, and I had no idea what she was talking about.’

‘The door with the barrels?’

‘She kept saying, “Remember, we saw Gavin pushing the wooden pallet and the barrels in front of the door?” but I couldn’t. After a while, she realized I wasn’t with her. I think she was shocked when she worked out that I’d never been part of this huge thing that had happened.’

She stops, looking at her hands.

‘What was the huge thing?’

‘She told me that when we were all playing Hide and Seek, she’d seen Gavin blocking a door in one of those half-finished houses on the building site. She didn’t really think anything of it until later, when people realized Lily was properly missing. She went back to the house where she’d seen him, but Mary and Robbie Murphy were already there, along with a man called Tom something and Della Burke and her daughter Fran. Fran was the neighbour I mentioned earlier, the one who was minding Lily the night Gavin broke in.’

I nod but don’t interrupt.

‘Anyway, they’d moved the barrels and there was nobody inside. She says she remembers Mary Murphy looking out of the window, shining a torch out there, and the sheer terror on her face as the search went on. But Aoife couldn’t stop thinking about the way Gavin made Lily cry, and then seeing him block the door.’

‘Why didn’t she tell anyone?’

‘She did. She told her parents, who went to Gavin’s parents. And they said there was no need for anyone to take it further, since Lily clearly wasn’t in that room. And that was that. That’s what I mean about things not being properly investigated.’

‘So you decided to reveal it in a blog post, thirty-three years later?’

‘Kind of, but I couldn’t do it in the end. Whatever he may have done, Gavin was my husband. I wrote posts hinting that there’s more to the story, but stopped short of telling what Gavin did that morning during the game of Hide and Seek.’

‘Is that what you meant in the blog post title – “The Locked Room”?’

‘Exactly.’

Not my locked room. Not me at all.