Sexuality is a fundmental, natural part of being human, for people of all ages. However, defining sexuality can be difficult. It may help to think about sexuality "as the expression of an age-blind desire for meaningful intimacy and connection with others."*
When you think about talking to your children about sexuality, think about the areas that you would feel comfortable starting a conversation about. Anatomy? Body image? Love? Sexual orientation? Media images of sexuality? These are all aspects of sexuality, that are related your child's sexual health. Start the conversation from a place where you feel comfortable, and work your way into the topics where you feel less familiar.
*From "Must We Fear Adolescent Sexuality?", Amy Schalet, Ph.D., Medscape, 2004.