It's partly the lack of solid walls, with the sense that, when you sleep in a field with strangers, and can hear the farting and the sighing, the whispered bedtime stories, the trips to the loo in pyjamas, we are all in it together.
"I was probably the only chief medical officer on the planet who knew how many children in his country were being read bedtime stories.
I go home and read the kids a bedtime story, it's not a glamorous life going to parties every night, your social life is shit.
The boy, aged eight, hit back: "You're not my father, you don't set my bedtime".
According to my mother, there is a chapter in Little Women in which the characters discover Father Christmas doesn't exist and her reading this to me at bedtime led to a direct question about the man's existence.
He looked after me at weekends when Mum and Dad were working, and he'd make me oatcakes smothered with Dairy Lea, and a cup of hot milk, before reading me bedtime stories.
We have tried rewarding him for not doing so, restricting fluids before bedtime and waking him in the night, but it hasn't worked.
This Christmas Eve, just like every year, we shall prepare for bedtime by hanging a stocking at the end of the bed, leaving a mince pie and a small glass of malt whisky for Santa (he prefers an aged Islay in our house; you can keep your sherry) and, of course, a carrot for Rudolph.
Some arguments are, by their nature, two-day events: too much is at stake to set an arbitrary bedtime deadline.
By the way, she hastens to add, she is around for her children at weekends, breakfast and bedtime.
After dinner, children choose their own activities until we get ready for bedtime; we may read a book with the child or talk about the events of the day, maybe give a hand massage to emphasise that we are winding down.
