Wotcher Chop!
I used Parking Vert a few years ago on a family outing to Le Mans.
Unfortunately late on Saturday night someone stole my Grandmother. And then on Sunday morning Uncle Wally went missing.
You have to learn from these things, and the following year I chained Nan to the rear bumper with one of those heavy duty motorbike security chains, and I'm pleased to say she never budged. It's very important to remember to unchain any relatives though, before you drive off.
H