For those who are interested to know what experts think parents should share with their preschoolers about sexuality, below please find some info. Having the knowledge is good though it does not mean you have to tail 100%.Please note that info are mostly from the western countries as Asian countries have minimal to begin with. Early childhood educators are trained in these and at degree and above level, some are required to read through research journals, etc and write papers as assignments.
Apply knowledge based on your discretion.
Sex education: Talking to toddlers and preschoolers about sex
By Mayo Clinic staff
Sex education often begins with a child’s curiosity about his or her body. Here’s how to set the stage for sex education — and how to answer your child’s questions.
Sex education is a topic many parents would prefer to avoid. And if you have a young child, you might think you’re off the hook — at least for a while. But that’s not necessarily true. Sex education can begin anytime. Let your child set the pace with his or her questions.
As children learn to walk and talk, they also begin to learn about their bodies. Open the door to sex education by teaching your child the proper names for his or her sex organs, perhaps during bath time. If your child points to a body part, simply tell him or her what it is. This is also a good time to talk about which parts of the body are private.
When your child asks questions about his or her body — or yours — don’t giggle, laugh or get embarrassed. Take the questions at face value. Offer direct, age-appropriate responses. If your child wants to know more, he or she will ask.
Many toddlers express their natural sexual curiosity through self-stimulation. Boys may pull at their penises, and girls may rub their external genitalia. Teach your child that masturbation is a normal — but private — activity. If your child starts masturbating in public, try to distract him or her. If that fails, take your child aside for a reminder about the importance of privacy.
Sometimes, frequent masturbation can indicate a problem in a child’s life. Perhaps he or she feels anxious or isn’t receiving enough attention at home. It can even be a sign of sexual abuse. Teach your child that no one is allowed to touch the private parts of his or her body without permission. If you’re concerned about your child’s behavior, consult his or her doctor.
Curiosity about others
By age 3 or 4, children often realize that boys and girls have different genitals. As natural curiosity kicks in, you may find your child playing "doctor" or examining another child’s sex organs. Such exploration is far removed from adult sexual activity, and it’s harmless when only young children are involved. As a family matter, however, you may want to set limits on such exploration.
Everyday moments are key
Sex education isn’t a single tell-all discussion. Instead, take advantage of everyday opportunities to discuss sex. If there’s a pregnancy in the family, for example, tell your child that babies grow in a special place inside the mother. If your child wants more details on how the baby got there or how the baby will be born, offer them.
Consider these examples:
How do babies get inside a mommy’s tummy? You might say, "A mom and a dad make a baby by holding each other in a special way."
How are babies born? For some kids, it might be enough to say, "Doctors and nurses help babies who are ready to be born." If your child wants more details, you might say, "Usually a mom pushes the baby out of her vagina."
Why doesn’t everyone have a penis? Try a simple explanation, such as, "Boys and girls bodies are made differently."
Why do you have hair down there? Simplicity often works here, too. You might say, "Our bodies change as we get older." If your child wants more details, add, "Boys grow hair near their penises, and girls grow hair near their vaginas."
As your child matures and asks more detailed questions, you can provide more detailed responses. Answer specific questions using correct terminology. Even if you’re uncomfortable, forge ahead. Remember, you’re setting the stage for open, honest discussions in the years to come.
Other resources selected after a quick browse over the internet, meaning no guarantee of whether the source is affiliated with any gay / religious / etc community as it will be too tedious to verify such affiliation: