Probably not. By definition molestation means an act where the offending party receives some type of sexual satisfaction. I'm not sure you can say any act by a six year old results in sexual satisfaction, although I could not be sure without more information about the boy.
If there is a problem some sort of counseling with a professional should be sought.
No one here can possibly offer anything useful or intelligent about what these facts add up to at this moment. We don't know anything but what you posted and you don't know much reliably.
You will want to talk constructively with the school, after you have talked calmly and constructively with your daughter. Not every act of affection -- even touching -- at that age constitutes "molestation" and you don't serve your daughter's healthy development by picking that as your starting point. You need to find out what the pre-incident relationship circumstances between these two children has been, in the observation of those who have been in a position to know, and to determine whether the facts give reason for concern or fear. Ask the school whether there are any experts on district staff that you can talk to if you are unable to come to any sound conclusions after talking with school staff. Over-reacting or reacting badly or inappropriately can cause additional and separate problems for all, so tread carefully, methodically, and constructively. Very possibly this is not a legal issue.
I don't see any legal or practical significance in your point about who communicated the incident to you. And the tags you selected here for this post evidence a serious need to dial down and get the facts and a rational handle on the matter before you move forward.
My responses to questions on Avvo are never intended as legal advice and must not be relied upon as legal advice. I give legal advice only in the course of an attorney-client relationship. Exchange of information through Avvo's Questions forum does not establish an attorney-client relationship with me. That relationship is established only by individual consultation and execution of a written agreement for legal services.
As usual, Ms. McCall's advice is direct and sound. Heed it.
Note, too, that "molestation" has to be for a sexual purpose - to arouse sexual interest in the victim, to arouse sexual interest in the perpetrator, etc. At the age of 6 it would be a biological oddity for the kiss behind a building between two 6-year olds would be to arouse sexual feelings since I doubt either of them knows what that really means.
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