So gargantuan thanks all round to the FLF lot for organising. Here's my runner-up entry - I meant to improve on it but never had the spare few minutes:
"Dear Son. In 9 years and 7 days you'll know this was my way of saying I love you. For now, please get on the bus. Don't look back."And here's the winner, from @_MyNameIsFaye:
"I urinated on to the stick and we sat staring at it. If two lines appeared you would propose. If one line appeared I would leave you."Brilliant stuff.