i think the terms are important for when they talk to a police officer or child protective services or whomever would interview them in the event that they were molested.
we all "touch their bottoms" all the time when we pick them up to boost them up to the top of a slide or whatever innocent touching goes on. WITH CLOTHES ON, of course.
very very few people should ever touch their unclothed vulva per se or their vagina or their penis per se. that should only be mom or dad or whomever trusted caregiver guardian, AND only in select circumstances such as putting ointment on a rash, especially as the child gets to preschool age.
that is the difference...
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