Nothing seemed to change much in the week or so after that trip. I didn't expect it to stay that way though, and sure enough, by the start of October, I started noticing little differences. For one thing, though Tommy carried on with his animal pictures, he became cagey about doing them in my presence. We weren't quite back to how it was when I'd first become his carer and all the Cottages stuff was still hanging over us. But it was like he'd thought about it and come to a decision: that he'd continue with the animals as the mood took him, but if I came in, he'd stop and put them away. I wasn't that hurt by this. In fact, in many ways, it was a relief: those animals staring us in the face when we were together would have only made things more awkward.

But there were other changes I found less easy. I don't mean we weren't still having some good times up in his room. We were even having sex every now and then. But what I couldn't help noticing was how, more and more, Tommy tended to identify himself with the other donors at the centre. If, for instance, the two of us were reminiscing about old Hailsham people, he'd sooner or later move the conversation round to one of his current donor friends who'd maybe said or done something similar to what we were recalling. There was one time in particular, when I drove into the Kingsfield after a long journey and stepped out of the car. The Square was looking a bit like that time I'd come to the centre with Ruth the day we'd gone to see the boat. It was an overcast autumn afternoon, and there was no one about except for a group of donors clustered under the overhanging roof of the recreation building. I saw Tommy was with them--he was standing with a shoulder against a post--and was listening to a donor who was sitting crouched on the entrance steps. I came towards them a little way, then stopped and waited, there in the open, under the grey sky. But Tommy, though he'd seen me, went on listening to his friend, and eventually he and all the others burst out laughing. Even then, he carried on listening and smiling. He claimed afterwards he'd signalled to me to come over, but if he had, it hadn't been at all obvious. All I registered was him smiling vaguely in my direction, then going back to what his friend was saying. Okay, he was in the middle of something, and after a minute or so, he did come away, and the two of us went up to his room. But it was quite different to the way things would have happened before. And it wasn't just that he'd kept me waiting out in the Square. I wouldn't have minded that so much. It was more that I sensed for the first time that day something close to resentment on his part at having to come away with me, and once we were up in his room, the atmosphere between us wasn't so great.

To be fair, a lot of it might have been down to me as much as him. Because as I'd stood there watching them all talking and laughing, I'd felt an unexpected little tug; because there was something about the way these donors had arranged themselves in a rough semi-circle, something about their poses, almost studiedly relaxed, whether standing or sitting, as though to announce to the world how much each one of them was savouring the company, that reminded me of the way our little gang used to sit around our pavilion together. That comparison, as I say, tugged something inside me, and so maybe, once we were up in his room, it was as much me feeling resentful as the other way round.

I'd feel a similar little prickle of resentment each time he told me I didn't understand something or other because I wasn't yet a donor. But apart from one particular time, which I'll come to in a moment, a little prickle was all it was. Usually he'd say these things to me half-jokingly, almost affectionately. And even when there was something more to it, like the time he told me to stop taking his dirty washing to the laundry because he could do it himself, it hardly amounted to a row. That time, I'd asked him: "What difference does it make, which one of us takes the towels down? I'm going out that way anyway."

To which he'd shaken his head and said: "Look, Kath, I'll sort out my own things. If you were a donor, you'd see."

Okay, it did niggle, but it was something I could forget easily enough. But as I say, there was this one time he brought it up, about my not being a donor, that really riled me.

It happened about a week after the notice came for his fourth donation. We'd been expecting it and had already talked it through a lot. In fact, we'd had some of our most intimate conversations since the Littlehampton trip discussing the fourth donation. I've known donors to react in all sorts of ways to their fourth donation. Some want to talk about it all the time, endlessly and pointlessly.

Others will only joke about it, while others refuse to discuss it at all. And then there's this odd tendency among donors to treat a fourth donation as something worthy of congratulations. A donor "on a fourth," even one who's been pretty unpopular up till then, is treated with special respect. Even the doctors and nurses play up to this: a donor on a fourth will go in for a check and be greeted by whitecoats smiling and shaking their hand. Well, Tommy and I, we talked about all of this, sometimes jokingly, other times seriously and carefully. We discussed all the different ways people tried to handle it, and which ways made the best sense. Once, lying side by side on the bed with the dark coming on, he said: "You know why it is, Kath, why everyone worries so much about the fourth? It's because they're not sure they'll really complete. If you knew for certain you'd complete, it would be easier. But they never tell us for sure."

I'd been wondering for a while if this would come up, and I'd been thinking about how I'd respond. But when it did, I couldn't find much to say. So I just said: "It's just a lot of rubbish, Tommy. Just talk, wild talk. It's not even worth thinking about."

But Tommy would have known I had nothing to back up my words. He'd have known, too, he was raising questions to which even the doctors had no certain answers. You'll have heard the same talk. How maybe, after the fourth donation, even if you've technically completed, you're still conscious in some sort of way; how then you find there are more donations, plenty of them, on the other side of that line; how there are no more recovery centres, no carers, no friends; how there's nothing to do except watch your remaining donations until they switch you off. It's horror movie stuff, and most of the time people don't want to think about it. Not the whitecoats, not the carers--and usually not the donors. But now and again, a donor will bring it up, as Tommy did that evening, and I wish now we'd talked about it. As it was, after I dismissed it as rubbish, we both shrank back from the whole territory. At least, though, I knew it was on Tommy's mind after that, and I was glad he'd at least confided in me that far. What I'm saying is that all in all I was under the impression we were dealing with the fourth donation pretty well together, and that's why I was so knocked off balance by what he came out with that day we walked around the field.

THE KINGSFIELD DOESN'T HAVE MUCH in the way of grounds. The Square's the obvious congregating point and the few bits behind the buildings look more like wasteland. The largest chunk, which the donors call "the field," is a rectangle of overgrown weeds and thistles held in by wire-mesh fences. There's always been talk of turning it into a proper lawn for the donors, but they haven't done it yet, even now. It might not be so peaceful even if they did get round to it, because of the big road nearby. All the same, when donors get restless and need to walk it off, that's where they tend to go, scraping through all the nettles and brambles. The particular morning I'm talking about, it was really foggy, and I knew the field would be soaking, but Tommy had been insistent we go there for a walk. Not surprisingly, we were the only ones there--which probably suited Tommy fine. After crashing about the thickets for a few minutes, he stopped next to the fence and stared at the blank fog on the other side. Then he said: "Kath, I don't want you to take this the wrong way. But I've been thinking it over a lot. Kath, I think I ought to get a different carer."

In the few seconds after he said this, I realised I wasn't surprised by it at all; that in some funny way I'd been waiting for it. But I was angry all the same and didn't say anything.

"It's not just because the fourth donation's coming up," he went on. "It's not just about that. It's because of stuff like what happened last week. When I had all that kidney trouble. There's going to be much more stuff like that coming."

"That's why I came and found you," I said. "That's exactly why I came to help you. For what's starting now. And it's what Ruth wanted too."

"Ruth wanted that other thing for us," Tommy said. "She wouldn't necessarily have wanted you to be my carer through this last bit."

"Tommy," I said, and I suppose by now I was furious, but I kept my voice quiet and under control, "I'm the one to help you. That's why I came and found you again."

"Ruth wanted the other thing for us," Tommy repeated. "All this is something else. Kath, I don't want to be that way in front of you."

He was looking down at the ground, a palm pressed against the wire-mesh fence, and for a moment he looked like he was listening intently to the sound of the traffic somewhere beyond the fog. And that was when he said it, shaking his head slightly: "Ruth would have understood. She was a donor, so she would have understood. I'm not saying she'd necessarily have wanted the same thing for herself. If she'd been able to, maybe she'd have wanted you as her carer right to the end. But she'd have understood, about me wanting to do it differently. Kath, sometimes you just don't see it. You don't see it because you're not a donor."

It was when he came out with this that I turned and walked off. As I said, I'd been almost prepared for the bit about not wanting me any more as his carer. But what had really stung, coming after all those other little things, like when he'd kept me standing in the Square, was what he'd said then, the way he'd divided me off yet again, not just from all the other donors, but from him and Ruth.

This never turned into a huge fight though. When I stalked off, there wasn't much else I could do other than go back up to his room, and then he came up himself several minutes later. I'd cooled down by then and so had he, and we were able to have a better conversation about it. It was a bit stiff, but we made peace, and even got into some of the practicalities of changing carers. Then, as we were sitting in the dull light, side by side on the edge of his bed, he said to me: "I don't want us to fight again, Kath. But I've been wanting to ask you this a lot. I mean, don't you get tired of being a carer? All the rest of us, we became donors ages ago. You've been doing it for years. Don't you sometimes wish, Kath, they'd hurry up and send you your notice?"

I shrugged. "I don't mind. Anyway, it's important there are good carers. And I'm a good carer."

"But is it really that important? Okay, it's really nice to have a good carer. But in the end, is it really so important? The donors will all donate, just the same, and then they'll complete."

"Of course it's important. A good carer makes a ............