Any parent knows - or should know at the very least - that the more intelligent a child is, the more careful you have to be about what you say in front of them.
The problem is that not only do we sometimes forget this, children usually have extremely good hearing - particularly when it’s something they’re not supposed to hear - and a remarkable ability to be ’within earshot’ when you’re not expecting it.
This was recently demonstrated in clear, unambiguous terms by the four year old daughter of one of my wife’s colleagues.
Bimbo Barbie, Brain-Dead Barbie, Boney Barbie...
You get the picture?
Naturally, her husband is rather more amused by this than she is.