Age-appropriate information must be given gradually and in stages.
Chastity is a virtue and a way of life.  Therefore, parents cannot wait until their child is a teenager and capable of sexual activity to address chastity education.  Chastity education is a formation process that must begin early in life, giving age-appropriate information gradually and in stages.  When children have been taught their entire lives that one loves in friendships and family relationships by being a gift to others, the introduction of sexual information and chaste love will naturally fit into place with the way they already understand relationships.  

The Catholic Church proposes guidelines for age-appropriate chastity formation according to three stages of growth:  Years of Innocence, Puberty, and Adolescence.  The Church does not define specific ages of when to move your child into the next stage of chastity formation because every child develops differently.  The Church exhorts parents to be cautious and prayerful in discerning the emotional, spiritual, and physical development of each child:  "Giving too many details to children is counterproductive.  But delaying the first information for too long is imprudent, because every human person has natural curiosity in this regard and, sooner or later, everyone begins to ask themselves questions, especially in cultures where too much can be seen, even in public"  (Truth and Meaning, 75). 

 

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General Guidelines

The Church urges parents to present the most intimate physical and emotional aspects of sexuality and chastity through personalized dialogue.  While it might be easier to simply give your child a book to read, a personalized dialogue provides a loving and trustful context for the information to be given.  It also gives you the chance to share your own personal witness of chaste love with your child.  

 

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Also, "Experience shows that this dialogue works out better when the parent who communicates the biological, emotional, moral and spiritual information is of the same sex as the child or young person.  Being aware of the role, emotions, and problems of their own sex, mothers have a special bond with their daughters, and fathers with their sons.  This natural bond should be respected.  Therefore, parents who are alone will have to act with great sensitivity when speaking with a child of the opposite sex, and they may choose to entrust communicating the most intimate details to a trustworthy person of the same-sex as the child" (Truth and Meaning, 67). 

 

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Aside from personal parental dialogue,  chastity formation sometimes requires parents to correct unchaste behavior.  The following tip from the Pontifical Council of the family could be applicable in the Years of Innocence (ages five through the onset of puberty), but oftentimes is applicable even in the earlier years of infancy.  I would like to present it here as a general guideline:

"From the earliest age, parents may observe the beginning of instictive genital activity in their child.  It should not be considered repressive to correct such habits gently that could become sinful later, and, when necessary, to teach modesty as the child grows"  (Truth and Meaning, 69).


The three sub-pages listed under the Age-Appropriate Information tab at
the top of this website elaborate on the age-appropriate information
for each of the three stages of growth in chastity: 
The Years of Innocence, Puberty, and
Adolescence. 

Resources:

* Truth and Meaning of Human Sexuality: Guidelines for Education Within the Family published by the Pontifical Council for the Family (paragraph 22 gives the objectives of chastity education, and paragraphs 65-67 give general guidelines for chastity education)