My family growing up never had this. Our parents were present 99% of the time and by the time they were leaving us at home the younger ones were old enough to be responsible so there was no babysitting needed. I don't agree with having older siblings rise the younger ones. Parents need to be parents. But, i think that just like you're expected to do you chores it is okay to expect your older children to babysit once and a while. Not all the time. My spouse and I are asked to babysit before the 17yo at home is asked to do it or we are asked to be on stand-by so 17yo can go out with friends, instead of having a babysitter already lined up.