We probably started by crawling, but the earliest I can remember we were walking - or stumbling, perhaps - through a makeshift desert. One big yellow tablecloth for sand, and a blue one if we wanted sea - but of course there isn't any sea in the desert. Paul always wanted it to be the desert, not the beach, because there was danger and adventure in the desert, and going to the beach was something we did once a year anyway.
We'd tie teatowels to our head, and walk slowly from one side of the tablecloth to the other. I suppose Mum or Dad would have been watching, but they aren't there in my memory. In my memory we were really in the desert - an enormous expanse, as far as we could see in any direction, hoping desperately to see an oasis on the horizon.
The game was mostly silent. Paul only ever said one thing, and I used to wait gleefully for him to say it. His pace would get even slower, and he'd fall onto his hands. That would be my cue to fall down too, trying not to laugh.
Paul would turn, raise his arm wearily, and shake his fist at the sky.
"The sun is not our friend!"
And then he'd fall flat, arms outstretched, eyes closed... until one or other of us started giggling too much.
We had practised death so many times. We had never practised grief. Now I don't know how I'm supposed to do it.