Toddlers are curious about everything. This is all a process by which they get to learn more about themselves and the world around them. It is a way by which they are broadening their horizons.
Children, whether boys or girls, are learning from every sense organ. They love to see, touch and feel, hear and smell things. They are constantly looking for new stimuli which can give them a chance to experience a new feeling.
The most cherished is the feeling of touch. It gives them warmth, security and love, and all children love being touched and fondled gently.
If your baby is having an erection, it is very normal. Once your baby has learnt to, he will enjoy touching himself and playing with his genitals. When your child is a baby, allow him to freely as this is one way of your baby discovering himself and his body parts. When he grows much older, you can gently distract him so he is occupied otherwise. Do not shout at your child or tell him that he should not be doing it.
As children start to grow, they get very curious about themselves and others. They will look at other children, and will want to know why children of the opposite sex are not like them.
In a while, your child will start to develop a gender identity depending on how he is being treated or called. Apart from how the are spoken to, they start to understand it in relation to their toys, clothes and also by looking at the differences between their mother and father.
Soon, your child will start to identify itself with the parent of the same sex. He will want to do the same things, we physically like them, and also start to talk in the same manner. If the parent of their sex is not around, they look to other adults who are of the same sex. Children start to imitate the parent and behave like the parent they spend most time with. They will dress like them and behave like them.
Allow your child to experiment. Let him learn for himself. Do not shout or dissuade your child. If your child asks you questions, answer each one patiently and never tell him it is not his business, even if it is about sexuality or gender differences. Tell him as subtly as you can, and in a way that he can understand it.