[Closed] what about a good old fashioned helmet debate

Kids in bicycle seats - I'm not sure at what point I stopped using helmets on my kids when they're on the bike seat (co-pilot limo) but I got a memo from my ex this morning requesting that I ensure helmets are worn in future..

Not a problem - anything for a quiet life

But I think I remember reading that in countries where bicycle use is more established, helmets are used less frequently than here so does anyone have any opinions on this subject?