I was brought up in quite a sexually-repressed way. I was one told by my mum that 'sex was for men'. No-one talked about it. TV programs featuring sexual content of any kind (not that much back in 70s!) was watched in agonised embarrassment. I learned the facts of life from school biology or from playground rumour - as did a lot of people of that generation I suspect.
DH was brought up very differently. No subjects were avoided so he had a quite different approach.
When kids came along I tried to be as open as possible (it wasn't natural for me to be so TBH). Hence my 15yr old DS and 13yr old DD will chat happily to me about masturbation, sex, contraception. I tend to deal with it by taking a deep (metaphorical) breath and just plunging in. DH sometimes is a bit taken aback himself. So I am wondering if perhaps it's isn't normal to be so open. Should they be more private? Should I be encouraging them to be more private? Help!