Elise shakes her head. ‘It’s hard to know. She could have been fifteen or sixteen, but she could have been younger.’ Her voice is low, her eyes imploring me to understand. ‘I’m so sorry.’

I’m silent. ‘You should have told us.’ In the circumstances, I can see why she didn’t, but this is the evidence we’ve needed. ‘I’ll send you over some phone numbers of lawyers – or if you see Chris, you could ask him. You can trust him,’ I emphasise, looking past her at Niamh, still in the kitchen. ‘If you’re worried about Niamh, or if you think she needs to talk to a professional, we can put you in touch with someone who can help.’

*

‘Sir, when Hollie took Niamh to Mason’s property, she saw some photos through a window – of girls. She also told Niamh that our doctor and Mason know each other very well, as she put it. But there’s more. A couple of weeks ago, Elise Buckley caught her husband looking at an image of a young girl on his phone. The girl looked fifteen or sixteen, but could have been younger.’

‘Why hasn’t she told us this before?’ the DI demands.

‘She said he’d know it was her who’d told us and she was frightened of what he’d do to her. I suppose it’s only knowing we’re holding him that’s given her the courage to talk.’

The DI looks at me. ‘We need to get over and search the Buckleys’ house, pick up his computer – see what else we can find. I’m going to step up the investigation into his finances, too. If he’s involved with Operation Rainbow, the chances are he’ll have a tidy sum stashed away somewhere. Buckley clearly knows more than he’s saying. I wouldn’t be surprised if his daughter does, too. But we’ll start with him.’

‘There’s more, sir. Apparently, Andrew Buckley had found out that Hollie was bulimic and used to self-harm. He overheard her talking with his son. He threatened to tell her parents and school if Dylan didn’t break things off with her.’

‘Who told you this?’

‘Niamh. After her brother died, she found a letter he’d left for Hollie.’

‘Did she say where the letter is now?’

‘She gave it to Hollie.’ I hesitate. ‘I can believe Andrew Buckley would have threatened them, and that it could have caused Hollie a great deal of embarrassment, but they were in love. Surely they wouldn’t have let that break them up?’

‘It does seem unlikely – unless there’s something else we don’t know.’ The DI pauses. ‘And it surely wouldn’t be a reason for Buckley to kill her, either.’ As we reach the door of the interview room, he stops outside. ‘Let’s see what he says.’

*