Pretty sure it's illegal in this country for anyone under the age of 15 left to look after younger kids. Maybe wrong.
there's no law concerning this nor how old kids have to be before you can leave them on their own. quite surprising as parents can be prosecuted for leaving them which makes the whole thing a pretty grey area
think the only law is that you're still responsible for any kids under 16 if you leave them with a babysitter who's also under 16