I haven't read through all of the responses, but I feel a need to reply. I am in your exact situation. Except, the boy is my brother and he's 19, not 17.
Clearly, I don't have the whole picture, so I'm probably going to be making a few assumptions, but bear with me...
My brother S has Downs. He is 19, but functions on about a 6-7 year old level for most things, a few things he's a little higher...maybe a 8 or a 9 year old. I'm 9 years older than him, so I was married and had kids while he was still very young. S began hitting puberty about 9-10 year old. Sadly, while delayed in nearly all other areas, it's not uncommon for a child with Downs to enter puberty earlier than 'normal.'
Despite being told from very early on to treat him as you would any child, my mother has not done that. At 19 she still fixes his plate for him, cuts his food, etc. She is convinced he is not capable of doing these things, even though it's clear to the rest of us he could. Sadly, this need to 'baby him' transferred over into sexuality issues when S hit puberty. She didn't have the "birds and the bees" talk with him. She would tell him to stop, but not explain why, or give him an alternative when he would 'hump' his stuffed animals in the living room while watching t.v. She's also very religious, so she considers masturbation sinful, so while saying, "that's something you should do in private" probably would have helped a lot, she would simply tell him to stop.
This has led to an overly sexual teenager. When I was pregnant with my first son, he came up and hugged me and kissed me on my breast. I yelled at him, and pushed him back, and my mother yelled at ME for getting upset with him. She has this deep-seeded need to protect his feelings from everyone, even when he is seriously in the wrong.
It's well known within my family (aside from my mother) that he has problems with boundaries. He's affectionate to a fault; hugs too long, kisses too much, stares inappropriately, etc. He's also aware enough to know my mother will let him get away with things, and will be sneaky and manipulative. HOWEVER...He is NOT being sneaky because he is a predator. He's being sneaky because he simply views these behaviors as something he KNOWS is wrong, but knows he can get away with, NOT because he's trying to get my child alone so he can molest him. Think of it as a 'normal' child sneaking into an R rated movie, or eating the entire package of cookies and lying about it. He knows it's wrong...but he doesn't equate it as being any MORE wrong than something like that. We had an incident a few months ago, similar to what you went through, except it was my oldest son. They got out of our site for 2 minutes, and my husband found S and my son in the bedroom, and my son had his pajama pants off. He was sitting in one chair, and S was sitting in another, and my son was adament that nothing had happened. But...it was enough to shake me to my core. I had a frank discussion with my mother, but it changed nothing.
So, we've had to take protective measures. I have explained to my oldest, in very clear language that he is NOT to be alone with S. We make sure that someone is in the room with S all the time. I make sure I change my toddlers diapers in a different room. Tickling is off limits, as is sitting on S's lap. My job is to protect my kids, and while I won't cut him off, I am on high alert when he is around my children. I've also made sure that they know to be very loud and vocal if S begins to make them uncomfortable.
Anyway...Sorry to have rambled for so long. I just know exactly how you're feeling. Even though I'm positive nothing happened, I felt shell-shocked and terrified at how close it may have come to happening. It's scary, and makes you feel powerless. I'm terribly sorry that you're going through this, and that your daughter experienced what she did. If you want to PM me, you're welcome to. It's something we've been dealing with for several years now.
Clearly, I don't have the whole picture, so I'm probably going to be making a few assumptions, but bear with me...
My brother S has Downs. He is 19, but functions on about a 6-7 year old level for most things, a few things he's a little higher...maybe a 8 or a 9 year old. I'm 9 years older than him, so I was married and had kids while he was still very young. S began hitting puberty about 9-10 year old. Sadly, while delayed in nearly all other areas, it's not uncommon for a child with Downs to enter puberty earlier than 'normal.'
Despite being told from very early on to treat him as you would any child, my mother has not done that. At 19 she still fixes his plate for him, cuts his food, etc. She is convinced he is not capable of doing these things, even though it's clear to the rest of us he could. Sadly, this need to 'baby him' transferred over into sexuality issues when S hit puberty. She didn't have the "birds and the bees" talk with him. She would tell him to stop, but not explain why, or give him an alternative when he would 'hump' his stuffed animals in the living room while watching t.v. She's also very religious, so she considers masturbation sinful, so while saying, "that's something you should do in private" probably would have helped a lot, she would simply tell him to stop.
This has led to an overly sexual teenager. When I was pregnant with my first son, he came up and hugged me and kissed me on my breast. I yelled at him, and pushed him back, and my mother yelled at ME for getting upset with him. She has this deep-seeded need to protect his feelings from everyone, even when he is seriously in the wrong.
It's well known within my family (aside from my mother) that he has problems with boundaries. He's affectionate to a fault; hugs too long, kisses too much, stares inappropriately, etc. He's also aware enough to know my mother will let him get away with things, and will be sneaky and manipulative. HOWEVER...He is NOT being sneaky because he is a predator. He's being sneaky because he simply views these behaviors as something he KNOWS is wrong, but knows he can get away with, NOT because he's trying to get my child alone so he can molest him. Think of it as a 'normal' child sneaking into an R rated movie, or eating the entire package of cookies and lying about it. He knows it's wrong...but he doesn't equate it as being any MORE wrong than something like that. We had an incident a few months ago, similar to what you went through, except it was my oldest son. They got out of our site for 2 minutes, and my husband found S and my son in the bedroom, and my son had his pajama pants off. He was sitting in one chair, and S was sitting in another, and my son was adament that nothing had happened. But...it was enough to shake me to my core. I had a frank discussion with my mother, but it changed nothing.
So, we've had to take protective measures. I have explained to my oldest, in very clear language that he is NOT to be alone with S. We make sure that someone is in the room with S all the time. I make sure I change my toddlers diapers in a different room. Tickling is off limits, as is sitting on S's lap. My job is to protect my kids, and while I won't cut him off, I am on high alert when he is around my children. I've also made sure that they know to be very loud and vocal if S begins to make them uncomfortable.
Anyway...Sorry to have rambled for so long. I just know exactly how you're feeling. Even though I'm positive nothing happened, I felt shell-shocked and terrified at how close it may have come to happening. It's scary, and makes you feel powerless. I'm terribly sorry that you're going through this, and that your daughter experienced what she did. If you want to PM me, you're welcome to. It's something we've been dealing with for several years now.
for you. 
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