In my own case, my younger sister's activities were not nearly scrutinized like mine were. My older daughter feels that I was more strict with her than with her younger sister. I was not more strict but I had some experience under my belt with my second. The girls were five years apart so things that came up with the second I may have already dealt with which was always helpful.
I think it varies from family to family. My youngest sister got into more trouble that I or my brother. And I don't think she did more than we did, she just did not even try to hide her tracks as well.
My youngest son, hardly even got in trouble. He was/is a homebody.
