My son caught playing with other boys parts

My seven year old son was at my sisters house for a weekend and was playing with another five year old boy.  Both boys were caught in the bedroom playing with eachothers private parts.  My son was caught sucking on the other little boys private part. My sister told me that they were both seperated and put in trouble. My sister told me that the other little boy has been caught doing this before.  I have also caught my son trying to get my four year old daughter to play with his private parts.  I am extremely concerned and dont know how to handle this.    This doesnt seem like normal sexual curiosity and not sure were he learned this behavior from.    

[Kevin Kennedy, Ph.D.]

It sounds like both of the boys have engaged in the behavior on previous occasions. Lessons learned - be sure to supervise him very closely. It's important that you set a very firm limit with him about this sort of activity. Let him know it is absolutely out of bounds for him to be touching another person's genital area or to permit anyone to touch him. Limit setting and education are the areas to focus on.

[gabeandharrysmom]

A related discussion, What goes over the limit of normal 5 and 6 yr old boy "play" was started.