.....and that child is therefore sent home from school for 14 days, the child is supposed to stay solely within their own house or garden for that entire period? They might be completely well for the full 14 days, but during that time, they can't take any walks. No bike rides. No drives in the car. If they haven't got a garden, they cannot go outside at all.
Many, many children are going to be in this position very soon - quite possibly multiple times - and it goes some way beyond the initial lockdown situation.