"Sperm donor!" yelled my nephew through the foam of the Atlantic rollers.
Well, you could have knocked me down with a polystyrene surfboard. (Indeed, a little-girl surfer did just that, as I took my eye off the swell.)
Jon Sevink is the founder, fiddler and now also manager of the radical folk-rock band The Levellers.
Finding myself recently on the same Cornish camp site and beach, I asked him to remind his forgetful uncle of the formative years in the job market during the lean, late Eighties before the band took off. We carried our Malibu (Jon) and wooden (me) surfboards up the beach and sat on a quiet dune.
"I haven't done a stroke of work since 1990," he claimed. This sounded odd. During our holiday he disappeared twice on gigs.
The Levellers have always been known as a hardworking band. This year they released their 10th album, made their seventh appearance at Glastonbury and ran the third of their own Beautiful Days festivals. "I don't count our music as work," he explained. For other people, it might count as hard labour, being stuck in a bus on foreign (this November) and domestic (September, October and December) tours, but for Jon it was the 1985-90 period he classifies as his "working and signing-on years".
"I never let myself believe that the band would actually take off," he confessed. The music business is not a level - or indeed a Leveller - playing field.
"I did seasonal work, as a paddling-pool attendant and a sperm donor."
For the first occupation he fished out floating lumps of pooh and chased off video-camera-toting paedophiles.
The second occupation was not in fact seasonal but twice-weekly (I told you he was a hard worker) and did not provide a full-time wage packet. "The Post Office was perfect for a struggling musician." As a student he once had a Christmas job in the sorting office, where he used his considerable abilities to separate first from second-class letters.
What he had now was the full Postman Pat scenario, without the van or the cat. It worked out well: up at 4am, clock on at 5am, finish by lunch time. This left the afternoons free for band rehearsals and the evenings for gigs. Sometimes he never got to bed.
"They were good, fine people there. You were left to yourself: you picked up your mail and went out with it. It was much better than going into an office and being shouted at."
The dogs were the downside: he would just chuck the mail in their owner's garden. It was the lack of sleep, and the band's success, which led him to pack it in after a year.
Perhaps his employers suspected he was not in it for the long haul. They never ordered up a uniform for him. Since he is about eight-foot tall and, say, 18 inches round the chest, it would never have fitted Postman Pat or anyone else.
Tour details on www.levellers.co.uk