Assessing sexual behaviour in children (6 to 11 years old)

Emotional development 

From the age of 8 on, children become aware of themselves as sexual persons, as well as others as potential affective and sexual partners. 

Acceptable behaviour - green flag 

Children know sexual shame and can both be insecure about and happy with their own bodies and appearance. Popularity already plays an important role. There is fear of being ridiculed. 

Significant others are no longer key figures. Relationships and friendships are increasingly important. Children experience a clear difference between being in love and friendship and are very loyal to friends. 

Children take responsibility, want to be useful and help others. 

They want to belong and need appreciation and recognition. There is also social anxiety. At this age, they turn against the opposite sex. 

Empathy continues to develop. Children have insight into the feelings, strengths and weaknesses of others and sometimes bully their 'equals'. 

Children engage in conversation, discussion and argument. They see cause-and-effect relationships. They can talk about their own feelings and, regardless of their own experiences, can sympathise with another person. 

Children can reflect on what they have done right and wrong. Behaviour is judged primarily based on the intention children have. They can apply rules of right and wrong and can adapt to rules. The internal conscience expresses itself more and more. At the end of this phase there is introspection and reflection. 

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

Mild bullying, making fun of others. 

Yellow flag response guidelines 

Being in love, relationships and feelings 

Acceptable behaviour - green flag 

Being in love can trigger intense feelings in children, without sexual feelings being linked to them. 

Being in love becomes the main expression of intimacy. Children can be in love with a peer as well as an adult. 

Children can become very self-conscious if they say they are in love. At the age of 8, children can describe what it feels like to be in love, and most of them have been in love themselves. By the end of this phase of life, most children have been in love at one time or another, and some children have a 'boyfriend' or 'girlfriend', usually someone from the class. This relationship generally only involves standing together at break time, or hanging around with a group of friends. There is barely any physical contact, including holding hands or kissing. They rarely spend time together without others being present. As children get older, there is more physical contact linked to being in love. The first careful touching, such as sitting next to each other, holding hands, arms around each other gives a very exciting feeling. Almost all children between the ages of 10 and 12 say they have been in love at one time or another, with 50% of the cases including kissing. 

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Experiencing being in love is not always mutual. Persistently urging the other person when the feeling is unrequited. 

• Putting the tongue in the mouth of a person when kissing.  

Yellow flag response guidelines 

Knowledge about sexuality 

Acceptable sexual behaviour - green flag 

From about the age of 7, an increasing number of children know that the genitalia also have a sexual function. The majority of 7- to 8-year-olds know that sexual intercourse is necessary in order to get pregnant, and how a baby comes out of the womb. Children ask more and more questions about sexuality. 66% of parents of 6- to 9-year-olds and 75% of parents of 10- to 12-year-olds are asked questions about sexuality from time to time.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

Asking about sex at inappropriate moments and places is moderately transgressive behaviour, due to the inappropriate context. 

! Enhanced vigilance is advisable in the event of: sexual knowledge which is not appropriate for the age. 

Yellow flag response guidelines 

Provocative or seducing 

Acceptable behaviour - green flag 

Children and especially girls sometimes dare to exhibit overtly provocative and seductive behaviour toward trusted adults. 
 
Climbing on the lap of trusted people and being cuddly.  

Green flag response guidelines 

 
Moderately transgressive behaviour - yellow flag 

• Displaying provocative and seductive behaviour toward non-trusted adults or older young people (Lolita behaviour). 
• Flirtatious talk.   
• Cuddling and trusting strangers without any restraint. 
• Annoying sexually explicit behaviour such as rhythmically stimulating the genitalia or showing them in public, and rubbing the body against people or furniture.  

! Enhanced vigilance is advisable in the event of:   
Demeaning or humiliating oneself or others with sexual games (for example, by wearing clothing in which breasts and/or private parts are visible).   

Yellow flag response guidelines 

Sexual interest - fantasies - desires - voyeurism 

Acceptable behaviour – green flag 

Children are driven primarily by curiosity and the desire for knowledge. Children want to see what they are not actually allowed to see precisely because it is forbidden.  

Children show less overt interest in each other's bodies. Nevertheless, many experiment with sex and bodies and gradually become aware of various (sometimes sexually suggestive) desires. 

Although some children have sexual fantasies at this age, the prevalence, frequency, content and associated arousal is unknown. In retrospective studies, adults often report experiencing their first sexual fantasies between the ages of 11 and 13.  

From the age of 10, interest in sex grows. Sex becomes an important topic of conversation, but the extent to which children are interested in sex varies significantly at that age. At this age, some children also come into contact with pornographic images.  

With more knowledge of the body and genitalia by the end of the childhood period, and more understanding of sex, children also think in their imaginations that sex is something they will soon be experiencing.  

They concentrate on a detailed knowledge of the body and genitalia (in their imaginations, a personal sexual contact is about to happen).  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Fears linked to sexual fantasies, violent fantasies. 
• Having a considerable fascination with sex, for example with online pornography. 

• One-off voyeurism, for example in toilets and shower rooms, without consent.  

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

• Conspicuously having a considerable fascination with sex, for example with online pornography. 
• Repeated voyeurism, for example in toilets and shower rooms, is seriously transgressive due to the repetitive nature of the behaviour.  

Red flag response guidelines 

Looking at or touching genitalia 

Acceptable behaviour - green flag 

Sexual activities, such as exploring and experimenting with trusted other children ages 6 or 7, are helpful in gaining knowledge and developing a sense of safety in sexual terms.  
 
Children aged 7-8 like to show their own genitalia and want to see other children's as well. They look at them and want to know how they function. They touch, inspect and play with the genitalia. 
 
Games with children of the same sex have a different character than games with children of the opposite sex.  
 
Children are driven primarily by curiosity and the desire for knowledge. Children want to see what they are not actually allowed to see precisely because it is forbidden.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• One-off sexual arousal in public by showing genitalia or touching the genitalia of others. 
• One-off attempt to undress others without their consent. 

• One-off voyeurism, for example in toilets and shower rooms.  

! Enhanced vigilance is advisable in the event of: fear of being caught. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

• One-off touching of the genitalia of children and adults with the mouth (oral contact). 

! Enhanced vigilance is advisable in the event of: 

• repeated sexual arousal by showing genitalia to strangers, gratification in public or online; 
• repeated attempts to undress others without their consent. 

Red flag response guidelines  

Severely transgressive behaviour - black flag 

Repeated touching of the genitalia of children and adults with the mouth (oral contact). 

Black flag response guidelines 

Masturbating - genital play 

Acceptable behaviour - green flag 

• Masturbation increases from the age of 8, especially in boys. On average, boys masturbate for the first time at the age of 10.  
• The age at which girls start masturbating is more variable; they are 8 years old on average. Self-gratification occurs and is linked to boredom, anxiety or arousal. From the age of 10 until puberty, 30 to 40% of boys and 18 to 30% of girls masturbate. 

• Masturbation is being aware that sexuality takes on a function in social situations (with and via others as well as in groups). 

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Masturbation in public or with insufficient efforts to ensure privacy. 
• Being conspicuously preoccupied with masturbation. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

Irritated genitalia due to masturbation. 

! Enhanced vigilance is advisable in the event of: not being able to stop masturbation. 

Red flag response guidelines 

Sexual language and sexual jokes 

Acceptable behaviour - green flag 

Children often draw genitalia.  

Children between the ages of 6 and 11 make up sexually suggestive jokes. They often say that sex is dirty, and make rhymes with sexually suggestive words.  

From ages 7 - 8 on, some conversations involve sexual knowledge and sexually suggestive jokes.  

Children aged 11 and 12 talk to each other more often about sex. They also watch pornographic images more often than younger children. They have already talked about sexually suggestive topics.  

Green flag response guidelines 

 
Moderately transgressive behaviour - yellow flag 

• One-off drawings about violent sexual acts (including rape). This is moderately transgressive behaviour because it is not appropriate for the child's age. 
• Making drawings about violent sexual acts in a situation that is not private (for example, in the classroom). This is transgressive behaviour due to the inappropriate context and because it is not appropriate for the child's age. 
• One-off use of sexually obscene language. 
• Making noises and drawings about sexual contact. 

• Having sexually explicit conversations once with others. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

• Repeated use of sexually obscene language. 
• Repeatedly making noises and drawings about sexual contact. 

• Repeatedly having sexually explicit conversations with others with a (significant) age difference. 

! Enhanced vigilance is advisable in the event of: after boundary setting and corrective reaction(s), still drawing pictures of violent sexual acts (including rape). 

Red flag response guidelines 

Walking around naked 

Acceptable behaviour - green flag 

Children develop a sense of shame when they undress. They become more introverted and prudish. For example, the bathroom or toilet door has to be closed.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

Intentionally exposing and showing buttocks (mooning) and genitalia. 

 
! Enhanced vigilance is advisable in the event of: anxiety when undressing. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

Regular lack of a sense of shame. 

! Enhanced vigilance is advisable in the event of: regular anxiety when undressing. 

Red flag response guidelines 

Online sexuality 

Acceptable behaviour - green flag 

• Children from the 5th and 6th grade explore sexual themes online. For example, 10% of children have already sent a sexy photo of themselves. 
• 69% of them sent a sexy photo of themselves only once. 21% did this several times and 10% do it more often.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

The percentage of children who receive a photo (18%) is higher than the percentage of those who send a sexy photo (10%). 

7% of children who were previously sent a sexy photo received it without the knowledge of the person in the photo. Sending sexy photos without consent is transgressive behaviour.  

35% of 9-12-year-olds in the Netherlands have already seen sexual images of, for example, an erection or a vagina up close, people touching each other's genitals or people having sex. 10% of 9–12-year-olds in the Netherlands have already seen a video of people having sex. Most children find sexually suggestive images mostly 'weird', but also 'funny', 'exciting' or 'normal'.  
They often see the images: 

• by searching for something else and accidentally coming across sexual images (through pop-ups, among other things); 
• by watching with someone else; 

• by someone else showing it.  

Some children specifically search for it. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

A small group takes sexual videos and photos of others and impulsively shares them, without understanding the possible consequences.  

Red flag response guidelines 

Severely transgressive behaviour - black flag 

! Enhanced vigilance is advisable in the event of: repeatedly taking and/or sharing sexually explicit videos and photos of others without consent and understanding the possible consequences.  

Black flag response guidelines 

Sexual games or sex games 

Acceptable behaviour - green flag 

Fully 25% of parents of 6- to 9-year-olds report having observed their child play 'doctors and nurses'. At the end of the childhood period, games are more often played in a group, for example, kissing games or masturbation games. Openly touching and caressing one's own genitals, and sex games with other children happens less and less in public. Around 50% of boys have sex games with other boys at the age of 10. They show or touch each other's genitals. 33% of boys have sex games with girls of the same age. 33% of girls have sex games with other girls. During girls' sexual games, objects are sometimes inserted into the vagina (18% between the ages of 10 and 12). At the end of the childhood period, these sexual games are less common.  

Sexual activities: (tongue) kissing and caressing. 

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Being persuaded or persuading others to participate in sexual games that result in negative feelings or guilt. 

• Sexually transgressive gestures; inserting objects into the vagina or anus. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

• Forcing others once and under (group) pressure to participate in sexual games or forcing sexually suggestive contact using power, coercion, authority, blackmail and manipulation. (Attempted) sexual intercourse with a peer, with consent. 

• (Attempted) anal sexual contact with a peer, with consent. 

Red flag response guidelines 

Severely transgressive behaviour - black flag 

! Enhanced vigilance is advisable in the event of: 

• hurting the other(s) during the sexual game;  
• (attempted) sexual intercourse with a younger child or older person;  
• (attempted) anal sexual contact with a younger child or older person; 
• (attempted) sexual intercourse or anal sexual contact with a peer without consent; repeatedly and under (group) pressure forcing other(s) to participate in sexual games or forcing sexual contact with the use of power, coercion, authority, blackmail, manipulation, violence and aggression (e.g., with a knife). 

Black flag response guidelines 

Gender and sexual identity 

Acceptable behaviour - green flag 

At the ages 5 and 6, children have very rigid ideas about gender stereotypes. They have clear ideas about what behaviour typically belongs to boys or to girls. 

Over the years, they become more flexible.  

From the age of 8, there is an awareness of oneself as a sexual person and of the other as a possible affective and sexual partner (sexual identity).  

The first exploration of sexual orientation starts at ages 8 to 10. Young people who develop a non-heterosexual orientation may already be aware of these feelings. 5% of gay young people have already told someone before age 12 that they are attracted to the same sex. Homosexual attraction and fantasies occur on average in boys at 9-10 years old and in girls at 10-11 years old.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

A limited number of children have feelings of gender dysphoria. Dissatisfaction with their biological sex usually disappears before the onset of puberty. The negative impact of this dissatisfaction can harm development.  

! Enhanced vigilance is advisable in the event of: fears, panic and serious doubt regarding one's own sexual identity. 

Yellow flag response guidelines 

More on the Developmental Chart 

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This document covers all behaviours, emotional expressions and methods of responding at any age. It also contains the sources of the scientific literature on which the Developmental Chart is based.