Really Rubbish Parenting

Many years ago, when I first moved to Devon, we hired a truck to move our few belongings (well, lots of them really, with two households merging into one). The truck was a proper one with a wide 3 seater cab. As a treat, the girls (aged 6) rode in the truck cab with me (with seat belts), while Evil Mel (Mel was the name of my ex, as well as the name of good, and present Mel, whilst Andy was the name of Good Mel's ex, Andy being my name too, so that keeps it all neat and tidy)drove the car with the Boy, aged 2.
Approaching Exeter, on the wide sweep of the A30 down from the Blackdown Hills, my (ex) step daughter apparently tried to open the window. She succeeded in not only opening the cab door, but also in slipping off the seat and disappearing from view. This is a child aged 6. The truck was travelling at 60 MPH on a sweeping right hand bend, so it really wasnt a good time to lean over and rescue said child. My daughter in the middle, froze. All I could see was fingertips hanging on. I screeched to a halt, in a few hundred yards, and miraculously, a small child clambered back on board.
Needless to say, the girls rode on to Dawlish in the car, which was following.
I didn't really think about it at the time. But I did throw up, sometime after we had unpacked, when the realisation sank in.
That step daughter is now I know not where (perhaps in Cornwall). She was a dreadful teenager but I am sure she is now a lovely young woman.

(Roxie news: she woke briefly yesterday (after an "it could be weeks/months prognosis"))