This girl is at least 10 to 12. New York State starts sex education at 9 to 10. If your kids are immature enough to not grasp the concepts of something as natural as their own parent's intimacy - the part of the relationship that ALLOWED THEM TO BE BORN, then that comes back onto you as a parent and nothing more. My kids have been making their own breakfast and getting themselves up for school on time since they were 8. Never forget how useless the average teenager is now compared to someone the same age in the 20s or 40s. 10 to 12 year olds are absofuckinglutely capable of grasping the concept of sex and it shouldn't be some mysterious fucked up thing you paint it as. Go on. Teach your kids that its something they have to GUESS over. Your daughter will be pregnant by the time she's 15.