Daughter buying clothing (undergarments)

My daughter is 15 & 13 but they still asks me to buy undergarments for them. I will let them choose the designs though. We have males in the house so sexy lingerie is a big NO for my daughters. They can get it themselves to flaunt to their husband when they got married in the future. I wear them myself but only in the bedroom and only for my husband. We're living in a world with sex maniacs so be extra cautious. I am also careful of their attire and how they sit when they wear shorts at home. Read too many incests, rapes, etc news. It's a crazy world out there!