Assessing sexual behaviour in preschool children (aged 3 to 6)

Emotional development 

Acceptable sexual behaviour - green flag 

A sense of shame gradually begins to develop in children. Pre-school children strive to copy the external features of significant others: hairstyle, clothes, appearance. Pre-school children identify with them and value the judgement of this group. 

Pre-school children accept rules of social behaviour and have a burgeoning sense of values and norms. 

Pre-school children develop empathy and recognise the feelings of others, but they still base everything on their own inner feelings. They can easily name their own feelings and are interested in stories, thoughts and feelings of others. 

They constantly ask 'why?' questions. They can adapt their language to the listener and are creative with language. 

They show feelings of guilt, regret and can see their own role in a conflict. They are more and more intrinsically motivated. 

Pre-school children express frustrations more verbally. They exhibit destructive and aggressive behaviour toward the source of frustration, or they can be withdrawn.  

Pre-school children can regularly be overcome by unpleasant feelings such as guilt, anxiety, feelings of humiliation, frustration or sadness.  

They observe sexually suggestive behaviour (such as kissing, fondling) without immediately understanding its content or scope. 

By the end of the pre-school period, children lose their egocentricity and are therefore better able to empathise with the experiences of others.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Negative feelings such as guilt or shame, fear, anxiety and confusion are more common in girls than in boys.  

! Enhanced vigilance is advisable in the event of: 

• fear of failure, very low self-confidence, impulsive aggression; 
• passivity or motor hyperactivity; 
• symptoms of sexual abuse: anxiety, nightmares, internalising and externalising problem behaviour, regression (bringing up the past); 
• immaturity, aggression and antisocial behaviour. 

Yellow flag response guidelines 

Being in love - frolicking and cuddling 

Acceptable behaviour - green flag 

Pre-school children frolic and cuddle. They hug or give kisses (including on the mouth) and sit on others' laps. Pre-school children gradually find that they are too big to sit on others' laps anymore. 

Parents observe that 5 - 6-year-olds touch or attempt to touch breasts. 

Pre-school children know a feeling of being in love. In research, this is described as a special friendship.  

Of the parents of 2–6-year-olds, 27% report that their child has previously been in love.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• A one-off attempt to insert the tongue into another person's mouth without permission while kissing. 
• Touching or attempting to touch breasts without asking permission.  

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

• Repeatedly touching breasts without asking permission. 
• Repeated attempts to insert the tongue into another person's mouth without permission while kissing. 

Red flag response guidelines 

Sexually suggestive language and games 

Acceptable behaviour - green flag 

There is further exploration of one's own body, and other people's bodies, and the associated feelings. This exploration phase often starts because of gaps in the knowledge of the pre-school child. 

As social control increases, this exploration gradually happens less in public. Doctors and nurses is played outside the school or out of view of adults, because children have been given the signal that these games do not fit into the social code of the school.  

At the age of 3, some children start their 'naughty word' phase, often linked to potty training. Children then often say 'poo' or 'willy' all of a sudden, usually meant to be funny or to elicit a response from the parent. 84% of parents of 2–5-year-olds say this often happens. Pre-school children tell each other naughty jokes or draw pictures of genitalia. 

Between the age of 2 and 3 years, children start asking questions about the differences between boys and girls (at 2 years), pregnancy (at 2.5 years) and birth (at 3 years).  

By the age of 6, children notice that adults are less open to answering questions than the latter claim. Children therefore start to turn more to their peers.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Involving other children in sexual games against their will. 
• One-off sexually explicit language, noises, drawings (lewdness) which is not appropriate to the context. 

• One-off sexually vulgar conversations with peers. 

! Enhanced vigilance is advisable in the event of: 

• Children involving younger pre-school children or toddlers in sexual games; 
• knowledge about sex which is inappropriate for their age. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

• Repeated sexually vulgar conversations with peers. 

! Enhanced vigilance is advisable in the event of: 

• using coercion or dominance to involve other children in sexual games; 
• repeated sexual harassment or humiliation, for example, constantly wanting to pull down another child's trousers; 

• repeatedly using sexually explicit language, noises and lewd drawings, which is not appropriate to the context. 

Red flag response guidelines 

Severely transgressive behaviour - black flag 

! Enhanced vigilance is advisable in the event of: intentionally hurting other children while exploring the body, for example by biting or pinching. 

Black flag response guidelines 

Looking at or touching genitalia 

Acceptable behaviour - green flag 

Pre-school children are primarily driven by enormous curiosity:  

• undressing each other and looking at each other's genitalia;  
• peeking into changing rooms; 
• watching how other children pee; 
• trying to touch the genitalia of the parents; 
• touching the penis of a dog or a cat; 

• asking adults if they can see their genitalia. 

In this way, children discover each other's bodies, play with each other's bodies, and have their first experiences of lust in the company of others. This almost always involves touching each other's bodies. Genital contact with the opposite sex occurs. A study found that over 50% of boys and 17% of girls had had genital contact with the opposite sex.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• One-off voyeurism when the context does not allow it or against the will of others. 
• One-off groping of others without consent. 
• Two children noticeably often playing with each other's genitalia, or a group of peers playing with each other's genitalia. 
• Attempting to have sexual intercourse with the consent of peers. 
• One-off requesting or offering oral sex to children on the same level. 
• Pre-school children sometimes pretend to do fellatio after seeing images of oral sex; they imitate the movements of oral sex, lying with their head on another pre-school child's genitals and moving their head up and down. 
• A child inserting objects into their anus or vagina, whether in the context of sex games or otherwise. 

• Experiences with oral sex are very exceptional. Studies show that anal or oral sexual contact occurs between boys. Among girls, oral sexual contact hardly occurs, if at all. 

! Enhanced vigilance is advisable in the event of: 

• arousal from showing genitals to strangers; 
• interest in pornography. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

• Repeated voyeurism. 
• Repeatedly groping others without permission. 
• Attempted sexual intercourse without consent. 
• At the child's own initiative, touching the genitalia of children and adults once with their mouth (oral contact). 

! Enhanced vigilance is advisable in the event of: 

• repeatedly being aroused from showing genitals to strangers; 
• serious interest in pornography; 
• touching or forcing exposure of genitals with coercion, blackmail, or manipulation; 
• creating fear or being threatening (with violence); 
• repeatedly inserting objects into each other's anus or vagina (during sexual games); 

• inserting sharp objects into themselves or others. 

Red flag response guidelines 

Severely transgressive behaviour - black flag 

• At the child's own initiative, repeatedly touching the genitalia of children and adults with their mouth (oral contact). 
• Repeated attempts to have sexual intercourse without consent. 

! Enhanced vigilance is advisable in the event of: forcing or imposing oral sex on younger children. 

Black flag response guidelines 

Self-gratification or masturbation  

Acceptable behaviour - green flag 

Many pre-school children sometimes touch their genitalia. To experience a pleasant feeling, they rub or play with their genitals. The intention is not sexual; a pre-school child plays with their private parts because it feels pleasant. 90% of parents of 2–5-year-olds sometimes see their child touching their own genitals.  

Roughly 10-15% of children already know the typical movements for self-gratification. Self-gratification also sometimes happens due to frustration or to compensate for boredom and lack of playmates. 

Sexual arousal in the form of blushing, sweating and heavier breathing also occurs in children.  

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Disturbing others by being noticeably preoccupied with self-gratification. 
• Self-gratification that does not fit the context (for example, in the classroom). 

• Isolating oneself or being absent (social isolation). 

! Enhanced vigilance is advisable in the event of: disturbing others with sexually explicit behaviour (for example, rhythmically stimulating the genitalia, imitating sex with dolls or peers (with clothes on). 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

! Enhanced vigilance is advisable in the event of: 

• compulsive self-gratification (without deriving pleasure from it); 

• irritated genitalia. 

Red flag response guidelines 

Walking around naked 

Acceptable behaviour - green flag 

From the age of 4, feelings of shame and prudishness develop: 'Close the door!'. 

Green flag response guidelines 

Moderately transgressive behaviour - yellow flag 

• Walking around naked if the context does not allow it. 
• Intentionally exposing and showing genitals or buttocks (mooning) in public. 

! Enhanced vigilance is advisable in the event of: 

• anxiety when undressing and exposing oneself; 
• absence of shame. 

Yellow flag response guidelines 

Seriously transgressive behaviour - red flag 

! Enhanced vigilance is advisable in the event of: 
repeatedly exposing oneself and being naked. 

Red flag response guidelines 

Gender identity and stereotypes 

Acceptable behaviour - green flag 

Pre-school children gradually realise they are a boy or a girl. They understand that boys later become men and girls become women. They can name the genitals from 2 years old. From the age of 2.5 years old, they know whether they themselves are a boy or a girl. 

By the age of 5, children know that gender is a constant. Knowledge of gender roles increases significantly at this phase. Children also begin to behave more in accordance with their own gender roles. Between the ages of 3-4, they realise that gender is a constant. 

Gender roles become important: "That's not a toy for a boy," "Hey, I'm not a girl," and "Those are boys' clothes". At the age of 6, these perceptions are rather rigid.  

For pre-school children, the reaction of others still has little impact on their self-esteem. By the end of the pre-school period, boys increasingly play with other boys, and girls with girls. This preference has existed for 6 years and only gets stronger after that.  

Green flag response guidelines 

 
Moderately transgressive behaviour - yellow flag 

! Enhanced vigilance is advisable in the event of: 
Feelings of gender dysphoria (dissatisfaction with the gender one was born and grew up with). 

Yellow flag response guidelines 

More on the Developmental Chart 

How is the Developmental Chart used? 

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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.