When I was 8, My dad moved in with his girlfriend, and about a month later, her son began molesting me, and this went on until I was 14. I finally got the nerve to tell. I am not going to lie...Im pretty sure my step-mom hates me now, and the worst part is...
He got away with it. He told everyone I was lying, and they believed him...even my OWN family believed him over me...the only ones who believed me, were my sister, and my mom. In the end, I had to move out into my moms...and my dads and I's relationship has NEVER been the same.

Now let me tell you what you can do for this child. Tell him that he is NOT alone, and that it is NOT his fault, and that he did the right thing by telling. He will probably feel "dirty" afterwards, so let him know he is NO dirty. Let Him know that nothing bad can happen to him now, because the people that love him wont let it. You need to be there for him, and let him KNOW he can trust you. He will undoubtedly now have some issues concerning trust, and later in the future, he might go through some depression.
Please be there for him. Because I know just how crappy he feels right now, and he may even wish he didnt tell. Please tell the parents to take him to a councellor, for someone he can "trust" to not tell his secrets.
But try to find one that will take interest in his interests. My councellor actually brought in his dogs for me to see, and after that he gained my trust.

I am so sorry. This is so hard on a family...just be there for him. but ACT normal....dont act like he has leprocy...he's still the same, loving little boy.