I was never able to talk with any family about sex at that age.

Certainly it is the time when the body is all fired up and hormones are racing. I hope you get to have that talk with him BCG because i am sure that you will be able to make a big contribution to his development.

Many boys would not be able to ask, you are being paid a tremendous compliment and shown great trust. I would think that you should give him a womens perspective about what is good in a relationship, about trust and caring and the little things that matter so much, about how a woman feels when she has a period and her emotional reaction to it. The mysteries of women some men never learn and you can help your brother and his future partners by giving him the insight.

Tell him about what is good for a woman sexually, especially about the clit, I didnt even know what one was for so long, sex ed never taught anything much about that except to say it was there. Teach him that sex is a wonderful, normal human activity that is a gift when indulged in by mutual desire and feelings for each other. That it is not right to force it but will happen when the conditions are right.