Almost 20 years ago my friend found in his mom's room a dildo and polaroids of his step dad naked.
Is it normal for a husband and wife to keep stuff like that with teens living in their house?
Is it normal for a husband and wife to keep stuff like that with teens living in their house?

If anything, your parents having a good sex life is something to rejoice about. Happy parents generally make for a happy home, and, as a child of a dysfunctional married couple and later a divorced household, I can personally assure you that when Mom and Dad are happy with each other, the home is happy.
Butyeah, it's absolutely normal.
There, I fixed it for you.