Sexual behaviour in children Sexual behaviour in children Advice for parents on healthy and unhealthy sexual behaviour in children and teenagers, including what to do if you're worried. Children now are more likely to see or come across sexual images and videos at a younger age than their parents would have done. This can be through films, music videos or online, including pornography. Every child is different and may become interested in relationships, sex and sexuality at slightly different ages. But as children get older, the way they express their sexual feelings changes.