Although it is sometimes hard to believe that someone we know or love is capable of sexually harming a child, we must remember that children rarely lie about sexual abuse. It is highly unlikely that a child would deliberately make false accusations about adult-like sexual behavior.
Recanting (i.e. a child claiming that sexual abuse did not happen when it actually did) is much more common than false reporting. What a child says can be unclear. Evaluating a child to determine the likelihood that sexual abuse has occurred can be extremely tricky and should be done only by a specialist. Sometimes, particularly in very young children, it is difficult to know if they are speaking about something that really took place, or exactly when it might have occurred. Be attentive, consider a family safety plan, and learn about other warning signs in young children. You might also consider the many ways the child could have been exposed to sexual images, language, or behaviors.
Sometimes you may hear only part of a story. It is typical that the story may change or evolve over time. This is not an uncommon pattern for disclosure in children, and does not invalidate their story. Be attentive, learn more about other warning signs to watch out for, and seek the guidance of a professional when needed.