Because emergencies are so rare. Many adults are quite unprepared for a lot of them as well.

It’s different if you were to leave like a 1-2 year old in the care of someone but it’s generally okay to leave a 5-10 year old in the care of a 14-15 year old. They mostly just need to feed them and make sure they go to bed.

Plus it gives the teens responsibility and some extra money to spend and it helps them get prepared for the future. Usually if it’s a super young one the teens tend to have first and courses suitable for young children as well or actual baby sitting certifications from a course of some sort.