I found this quote rather amusing, "I think the wife/children would object
to switching lights on/off all day long."
Do they cope with flushing the toilet or have you arranged for that to
continuously flush?

Good idea! I am forever flushing the toilets for the children.

The problem with the lights is that not all the children can reach the light
switches. Also the kitchen is a thoroughfare between other rooms (it has 8
doors leading from it).

I suppose a PIR type of switch would be possible - we have them in the
offices where I work. They dim the lights out after about 20 mins of no
movement.

I was wondering about a PIR. Perhaps driving some small lights on the
skirting and with a 10-20 minute timeout. (Oh no not more lights!)

Colin