‘You read about it?’ I ask, stunned by her words. ‘What do you mean? Do you mean you planned it? Jesus Christ, Kathleen!’

‘No!’ She blinks at me, eyes wide before she casts her gaze downwards again. ‘Well, not really. I’d researched it but, you know, half-heartedly. It didn’t mean anything. I didn’t expect to … Well, I didn’t think I’d ever do it. I just wanted to know how, in case things got really bad for him.’

‘For him?’ Heidi snorts. ‘In case things got bad for him? What about the rest of us, Kathleen? Did you ever research how you could save us if things got really bad?’

Kathleen shakes her head. Brushes the tears from her eyes. What little trace of make-up she had been wearing has now been rubbed clear.

‘He was my brother,’ she says mournfully. ‘You can’t possibly understand. I’m not saying he was perfect. God knows he wasn’t. God knows he did some things that were unforgivable, but he was still my big brother. I still loved him. You can think that’s wrong all you want, if that’s what makes you happy …’

‘Nothing about this makes us happy,’ I tell her. ‘Nothing at all.’

I’m trying to take in everything that Kathleen is saying. To take in her twisted loyalty to Joe even though she knew what he was capable of. Even though she had moved hundreds of miles away, he still had this pull over her. She still felt compelled to come back to him in the end. She still loved him. She wanted to help him in her own way. In the end.

I think about my own relationship with him, how he retained that same pull over me, too. How he’d been able to summon me back into his life, too. That he had kept Heidi in his web all this time. Despite everything he’d done.

I find myself shaking. ‘Nothing at all about this makes sense. You loved him, you say, but you were the one who killed him. You can try to dress it up as a mercy killing if you want, but you murdered him.’

She winces at the word. Rubs her temples. Perhaps all this is giving her a headache. God knows my own head is starting to thump right now.

‘I never wanted him dead,’ she says eventually, the word ‘dead’ almost a whisper. ‘But I’d seen this before. This cancer. How it eats away at people. The death it gave my father.’ She shakes her head as if trying to shake away the memory. ‘You were so young at the time, Ciara, I doubt you even remember it. But it was horrific, and I didn’t – God, I just didn’t want to see Joe go through that. No matter what he’d done.

‘Heidi, you must understand? Your poor mother. You saw what cancer did to her. How it ate away at her. No one deserves that. If Joe had been an animal he’d have been put to sleep and spared his misery.’