If a child seems confused about their gender, it's normal for parents to feel puzzled or worried. But it's important to support your child and not to jump to conclusions.
It's common and natural for very young children to show an interest in clothes or toys associated with the opposite gender.
Children under five have little awareness that certain preferences are associated with one gender or other. If a three-year-old boy enjoys dressing in his sister's clothes, this probably means nothing in terms of how the child feels about his gender.
Even among older children, it's not uncommon for boys and girls to identify with the opposite gender or to say they want to be the opposite gender.
"This is probably not because gender-variant behaviour is more common in boys but because a little girl who's a tomboy tends to be less of a concern than a little boy who plays with Barbies."
Parents tend to worry more about gender-variant behaviour in little boys because it presents more of a challenge to our assumptions about gender.
Will my child grow up to be transsexual? Very few children who seem to be confused about their gender go on to live full-time as the opposite gender, or to be transsexual, as adults.
In most cases, the gender variant behaviour or feeling disappears as the child gets older.
Children who do continue to experience gender variance as they get older will develop in different ways. Some may feel they don't belong to any gender. Others may want to dress in the clothes of the opposite gender from time to time or on a regular basis.
Only a small number who have persistent and strong feelings of belonging to the opposite gender end up living full-time in the opposite gender.
When should I seek help for my child? "If your child is very strongly identifying with the opposite gender, to the point where it's causing the child or the family distress, seek help.
"Signs of distress in a young person or child can include self-harm, destructive behaviour and depression."
For young people who feel strong and persistent discomfort about their gender, puberty is often a very difficult time. The physical changes that occur at puberty can increase feelings of unhappiness about their body or their gender.
If your child is strongly identifying with the opposite gender, it's best to get help before puberty begins.
If the feelings of gender discomfort persist to the extent that your son or daughter wants to live full-time in the opposite gender, careful preparation needs to be made with the school and any clubs or groups that your child attends.
Who can help?
For medical help, first visit your GP. The next step is usually referral to a local CAMHS (Child and Adolescent Mental Health Service) team, where psychological help will be offered to your child or teenager. This may involve working with the whole family, and sometimes with the school as well.
Depending on what services are available locally and on what your Primary Care Trust is willing to fund, some young people are referred to the gender identity service at Tavistock and Portman NHS Foundation Trust in London. This is the only medical centre in the UK that specialises in helping children with gender variance.
Many parents find that talking to other people who've had similar experiences is a great help in terms of finding out more about gender variance, and receiving support.
The charity Mermaids has a telephone helpline (020 8123 4819, Mon-Sat 3-7pm), which parents can call for advice, information and support. The Mermaids website also has several real stories by young people and their parents.
In what ways can I support my child?
Sometimes, children worry that if they tell you how they feel, you won’t love them any more.
Mermaids' key advice to parents is: "Accept your child and let them know that no matter what their preferences are, no matter how they feel, you support them and love them."
Even if you feel concerned, try to be relaxed about cross-gender behaviour in your child. It's important that children don't feel judged or rejected because of who they are.
If you feel anxious or uncomfortable, you're not alone. You may blame yourself because you think it’s your fault. But gender identity is nobody’s fault.
Bullying at school is often an issue for children and teenagers who behave in ways that don't fit into traditional ideas about gender roles. At primary school, the other kids may not want to play with them because "they don't act like boys" or "they don’t act like girls". Secondary school can be even tougher.