During the toddler years (when a child is 12-36 months old), big changes happen for children—and so also for their parents. Most children start walking before or during the toddler years. Other physical skills also develop during this period. For example, your child will start being able to control her movements more and more each month. She will learn to use her eyes and hands together, for example, to roll a ball towards you. Toddlers also usually make progress in toilet training, so that your child will probably start to grow out of diapers and start using the toilet.

As your child enters the toddler years, he becomes more and more interested in exploring the world. He may seem to get into everything, or to ask “why?” over and over. He will start to figure out ways to deal with the stress of being away from you. He may use things like blankets, dolls, or stuffed animals to help him feel better when you are apart, whether that is at bedtime or during daycare. At the same time that your child is showing more independence, he will also continue to rely on you to help him cope with hard or painful situations.

Early in the toddler years, most children see themselves as the center of the world and have little understanding of how to be social with others. Toddlers start to develop a sense of how to be social by interacting with their parents and playing with other children. Through these interactions, toddlers start to become aware of what people expect and how people behave. They start getting a sense of what is expected of them and of others.

As toddlers mature, their ability to think increases. Toddlers want to understand things going on around them. They start to observe and to copy the behavior of others at this stage. Toddlers also begin to recognize patterns in everyday life and will expect things to follow certain patterns. For example, a toddler will recognize that her family eats dinner after mom gets home from work and will learn to expect to eat every day at that time. Toddlers may be fiercely strong-minded in this stage and show a strong will. They will often want things to go their way, and will be upset if things do not. They are also able to make simple plans and goals.

During the toddler years, most children start to understand words and how to use them. When children are between two and three years old, they begin to use language as a social tool to explain how they are feeling (for example, hungry, itchy, sad), to ask for what they want, and to find out more about the world. Sometimes toddlers feel frustrated when they can not get you to understand what they are trying to say.

One way children may let you know their feelings and ideas is through their play. If you watch your children play, you can often learn how they are doing and what they are thinking about. For example, a child might use a doll to act out what he remembers most clearly from an important doctor’s visit. (One mother remembers her young son getting ready to play “doctor” with a friend by pulling out a ruler to measure their penises—something that happened every time he went to the doctor.) Or a child may pretend a swing at the park is an airplane and she is going to visit her grandmother. If a child acts something out over and over again, it may be a clue that she is confused or stressed, and she may benefit from having you play with her and talk with her.

It is sometimes difficult to believe that children start to get a sense of right and wrong when they are just toddlers, but it happens as children see what is labeled “good” and what is labeled “bad.” This process of learning right and wrong is called “moral development.” Children at this age try to figure out how to get what they want (for example, by being “good”), and they also try to figure out how to please their parents.

During the toddler years, children begin to develop a sense of who they are, and how that may be different from who other people are. When your child looked in a mirror when she was younger, she just saw a moving image. But during the toddler years, usually a child discovers that the image in the mirror is her, and not someone else. She begins to understand who her family members are, and how she is related to them; she learns who is her sister and who is not her sister. She begins to understand why she has the last name that she does, and she may start to understand that she is considered a girl, like her sister, and not like her brother. She also starts to understand that what she wants is not always what her parents want. All of this is called the development of “self identity.”

In general, children have a sense of being boys or girls by about two years of age. Children begin to understand the difference between genders in many ways. Since children are told that they are either a girl or a boy by many people, they may attempt to fit the labels given to them. Children get cues about what counts as “appropriate” for their genders by watching the people around them, and by seeing how people treat them when they act like a girl or like a boy. They begin to notice that people are divided into two basic groups—boys/men and girls/women—by the way their voices sound, by the way they dress, by the way their hair is styled, and by the roles they play. If a toddler has seen people naked, he may also notice how most boys, men, girls, and women look, and he will begin to see how one’s gender identity usually matches one’s physical sex.

During these years, most children become interested in playing actively with other children. The curiosity they have means that they are also curious about their own bodies and others’ bodies. Sometimes they’ll be curious about their own genitals and the genitals of children they spend time with. This is common in nearly all children.

Some toddlers may see differences in genitals, while others may not notice the differences until preschool or after. Whether or not you see your child having this curiosity, it is a good idea to start letting your child know it is okay to talk about his body. Many parents of children with DSD say that the earlier you start talking with your child about sensitive topics like genitals, the easier it will be to talk more about gender, sex, and sexuality as your child grows. You can start talking with your child about his or her genitals when you are changing a diaper or helping the child use the toilet. You can occasionally say simple things like “point your penis toward the toilet water so the pee-pee goes in the bowl,” or “after you poop, wipe your bottom away from your vagina like this.”

In this way, you slowly start to give your child the language she will need to talk about her body. Do not try to push more information on your child than she is ready for. Take cues from her by listening to her questions and concerns, and answer those. Sometimes your own worries about her need to know or not know more will cause you to give too much or too little information. If you remember to go slow, take a deep breath, and listen closely to what your child is asking, you can be thoughtful in how you answer what she is really asking. You may need to teach a few new words as you answer questions.

A toddler will not be able to understand all the details about his DSD, but you can start to tell him about how most girls have clitorises and vaginas, and most boys have penises and scrotums, and that some people are different. You can start to explain how your child looked when she or he was born.

You may find that your three-year-old asks questions that catch you off guard, so it is helpful to think about and prepare for questions that your child might ask. Questions from toddlers are often about how their genitals function and why their genitals look the way they do. Here is an example of a question that a three-year-old might ask and a suggestion about how to answer. In this example, the child is using the word “pee pee” to talk about his penis.

If your child has had genital surgery, now may be a good time to start explaining that part of the reason your child’s genitals may look or feel the way they do is because a doctor changed them when the child was younger. You can sometimes use a doll or a stuffed animal to explain a little bit about how surgery happens. Again, follow your child’s lead about what she or he wants to know, but don’t try to hold back this information when it could naturally come out. The earlier you start talking with your child about his or her body, the easier it will be to keep the conversation going as he or she grows.