I have one younger sister and we so fall into the birth order thing. She is so bubbly and sweet but temperamental. And I'm so serious and nitpicky and academic.
I do feel like my parents are lenient with me but I don't do much publicly against their wishes so there's not much to be lenient about. My sister gets in trouble more than I do because she is more impulsive but she is also forgiven more easily and more adored. Which also makes sense because she is just as adoring back. I'm more reserved when it comes to my family. I feel much closer to my friends.