Celtic knot heart design

Mrs Okonedo in bed nine has asked for her knitting again. You find it in the locker: a grey cardigan sleeve, half done, the cable running in and out like a river under a bridge. Her eyes are too clouded for it now, so you sit on the edge of the plastic chair and follow the stitches for her. Over, under, over, the way her daughter taught her in a kitchen you have never seen.

Somewhere past four she tells you the pattern is called a true lover's knot, and that her mother would not let her wear one until she had finished a sampler of plain stitches. You ask whether the knot ever comes undone. She laughs, a dry sound, and says only if you pull the wrong thread. By half five the sleeve is finished, the loops closed tight at the cuff, and you tuck the ends in while the sky over the car park turns the colour of dishwater.

Before you go she asks you to draw it for her on the back of a observation chart, and you do, one line that never lifts from the paper. It takes three tries. When you finally get it right, the line comes back to where it started without a break. She holds the chart up to the window, nods once, and says that is the trick of it: you can go all the way round and still end up exactly where you began.