I mourned with the writer, but I was also intrigued. Who was she? How did the boy die? What really happened? And I wanted desperately to know that she was now doing better, that the words of reassurance she had written were true, that she had found a way to live with her grief and even to enjoy her life once more.

I was just plain curious. Curious to know who she was, what she was like, curious to know what had happened to her son. I had always thought of drivers who slow down to look at roadside crashes as intrusive rubber-neckers, but perhaps that element of curiosity has a more complex motivation: if I know how that crash occurred, I could avoid the same thing happening to me. And of course I am thankful that the accident has not happened to me. And somehow this letter from an unknown mother – a mother whose whole life had been absorbed in her son’s, and who had lost him in some appalling way – represented something of this car-crash mentality. The uneasy blend of curiosity and sympathy seemed to react together and produced not only a cautionary tale but a captivating mystery.

A few days later I called my friend the dog-walker for a chat, and the conversation soon turned to the letter in the bottle. While she too wanted to know more, I sensed that for her it would just remain one of life’s mysteries and that she was trying to put the bleak message out of her mind and get on with her life. For me it was different. The letter continued to haunt my thoughts over the next few weeks, and gradually the desire grew in me to find out more. Could the mother be found?

I was plagued by unworthy emotions: I wanted to know how Maurice had died; I wanted to know what his mother was like; I wanted to know whether I could track the origin of an unsigned letter in a bottle. I wanted the writer to know that the bottle had been found intact and beautiful on an English shore and that I had read her letter. I wanted to reassure myself that she was all right, that the optimistic impulse at the end of the letter had lasted. I wanted to know that there was life after death; that it was possible to recover from such an event, if not unscathed, then at least able to continue a meaningful existence.

And if, by some amazing piece of detective work or good fortune, I did find her, how would I approach her? As a mother? But didn’t I run the risk of seeming to gloat about my living children, while she mourned her dead son? Would I turn up on her doorstep, bottle in hand, smiling brightly? Would she be at all curious about who had found her letter or annoyed that I had interrupted its journey? Would she be pleased that people who cared had found it? Had she really meant it to ‘stay forever rocked by the ocean’, or had she wanted ‘all strangers’ to find it and share her emotions, as she also said in her letter?