Josie visited on Thursday morning. She phoned me to say she was outside, having picked up shopping for us and Mrs Whittaker. Darla had gone next door to take Roger for a walk. She waved from a distance—the asthma enough of a deterrent to stop her coming any closer.

Josie gestured towards the back garden. I had enough space for us to maintain a two-metre distance. "How are you?" she asked, standing in the shade of the evergreen magnolia and its expanse of waxy green leaves. "Have you noticed any symptoms yourself? Cal says you're okay?"

Ah. They were in contact with each other about me. To be expected, I guessed.

I shook my head. Josie belonged to the school that believed exposure to a bit of dirt and germs strengthened the immune system. Mine, as a result, should be weak and lazy because I never allowed it to engage in small scale battles thanks to my obsession with cleanliness.

Perhaps this time, I was right. Nothing so far symptoms-wise. Cal reckoned if I hadn't developed the telltale dry cough and heightened temperature by now, I wouldn't.

There was also that other conversation I had with him this morning when I called to update him on Tom's condition.

"New Year," he said, "didn't you go skiing in Italy?"

Yes. A last-minute thing escape I'd booked two days beforehand. I'd flown out to the Dolomites on the 30th and returned five days later, exhausted and with a nasty cough that lingered for a week. At the time, I put it down to exposure to other people's germs while flying.

"Any other symptoms?" Cal asked when I told him about it.

The cough had been a nuisance, but not enough to stop me going into work, the thought of which made my skin crawl.

"A headache and dry eyes," I said. "Cal—I went into the office. What if I..."

Spread it all around. Passed it onto another fellow asymptomatic who then visited an elderly relative.

Cal waved a hand. "No-one knew about coronavirus at that point. The WHO didn't declare it a pandemic until 11 March. In France, they've been re-examining some of the deaths originally certified as down to pneumonia at the beginning of the year. It's not your fault. But what it does mean is that in all likelihood you contracted the virus and built up a degree of immunity to it. We won't know until the antibody tests are available.

"Be cautious, though. There's not enough evidence having had the virus once provides long-lasting immunity."

Josie nodded when I told her Cal's opinion. "How is Tom this morning?"

Not good. I'd stayed with him last night, dragging the mattress off the single bed in the other room, and coaxing him to take deep breaths when the coughing took over. When I asked if I should call a doctor, he shook his head. No, the words vehement. Leave the NHS to deal with the vulnerable and the old.

Josie shifted from foot to foot. Her questions sounded distracted—a woman with something on her mind.

"Spit it out," I said, "whatever it is you feel you need to tell me."

She sighed. Darla had appeared at the other side of the garden, Roger on his lead beside her. The dog looked towards our house, his tail wag half-hearted. Wondering where Tom was? Darla being here signalled how seriously Josie took her mission to look after Mrs Whittaker and me. Her daughter should be at her laptop studying. Darla's private school had made the unusual decision to go ahead with the exams, due to start in a week's time.

"Mum, I don't think you should—"

Josie whipped around to face her. "What?"

"Say anything," Darla burst out, the words loud enough to make Roger glance up at her in alarm. "The Garda guy didn't say for sure, did he?"

Equidistant from them both, I switched focus from one to the other. "What is going on?"

Josie glared at her daughter. "Darla, were you earwigging last night when I was talking to dad?"

"No shit, Sherlock."

"For goodness' sake! You have no right to listen in to private conversations. And don't swear either."

"Stop it!" I raised my voice as they both turned towards me, angry expressions mirrored. "And keep you voices down. Josie, what were you talking to Alastair about?"

Was any of this out of the blue? What about that conversation with Tom's mother when she'd mentioned the assault I'd never heard Tom talk about? The Garda was Ireland's police service. A serious assault would attract their attention.

My sister let out another massive sigh. Roger, who had been walking as far as the constraints of the leash allowed, dropped onto his front paws. A dog who realised he might be here for a while. And much as my niece had begged her mother not to say anything, the prospect of drama for an excitement starved 16-year-old was too enticing to miss. She wasn't going anywhere.

Josie pushed her glasses up her nose. "You know I want the best for you. I'm aware," she gestured behind me at the far too big house, "that you've locked out other human beings for a long time. "

Darla, solemn-faced, nodded. It is something when your teenage niece views you as a friendless saddo.

"And that makes me reluctant to interfere this time."

"Never stopped you before," I snapped, regretting the words the second they left my mouth. Josie, the half-sister who had always looked out for me. Despite our family circumstances, me born to the woman who'd had an affair with her father while he was still married to her mother. The lawyer who gave me solid advice and supported me when my father tried to hijack my inheritance.

The one who, along with my mother, encouraged me to return to Glasgow, when what I was doing in London burnt me out. Josie hadn't known what hand happened in London as I told no-one, but I'd never underestimated Josie's detective skills. If she found out what had gone on during that awful year, she said nothing.

"But I've mulled over what I've found out, and I think—"

"Spit it out," I repeated, "before I die of boredom."

Childish of me. She sent me a withering look before setting out the story her Garda contact told her. He worked in the Irish equivalent of the CID, a plain clothes detective rather than a bog-standard copper. Five years ago, a Dublin hospital alerted officers when a man was brought in, barely clinging to life following a savage beating.

"Tom," I said. "I know this already." Albeit, not from the horse's mouth.

"No, not Tom," Josie shook her head. "This guy was in his 40s. Anyway, he was in intensive care for weeks. The doctor said later it was a miracle he escaped without permanent brain damage."

An all too vivid image—a man on the ground, his clothes scuffed with dirt while others (it had to be more than one) stood over him, their faces twisted into snarls, fingers curled around batons or baseball bats. The thump of wood on bone. Screams that rent the air.

"What... what does this have to do with Tom?" I whispered, my eyes flickering automatically upwards towards the bedroom that overlooked the back garden.

"By the time the man was capable of being questioned," Josie continued, "he claimed he didn't remember enough or see anything. Men coming at him in a dark alleyway—that kind of thing. But the detectives who did a bit of digging in the case uncovered an accusation against the man some years earlier. He was never charged."

I closed my eyes, knowing what she was about to say. I might have swayed on my feet.

"Rape," Josie added, "the woman's name was Docherty. She was very young at the time. Word on the street, the detective told me, was that her family took the law into their own hands."

"Are you okay, Aunt Sophs?" Darla jumped in. "You shouldn't have opened your mouth, Mum! That Garda guy wasn't 100 percent sure, and anyway, my feeling is the man des—"

"Thanks for the shopping, Josie," I said, "I'll be in touch."

Darla remonstrated with her mother. Josie brushed it off. I pivoted and headed back to the house.

"I told you because it relates to a violent crime!" Josie shouted after me, the words ringing in my ears as I let myself in through the back door.

What now?