Thanks guys, no, like David I wouldn't trust any of my wife's relatives (or mine, not that any were present, I only have a few and they're all interstate or live too far away) with any of my bikes, knowing how hard it is to find good parts to fix them again, if the inevitable happens.
No biggie, I agreed to fix my brother in law's ancient Suzuki RM125 which just has some crap in the carb (I've cleaned it before) and change the sparkplug on his motorised tricycle that I gave him for Christmas a few years ago after he lost his car license for DUI. The BBQ went well, everyone had plenty to eat and drink, so life is good, and I can rest again until this time next year.