The child sex abuse case against former Penn State defensive coordinator Jerry Sandusky is disturbing on every level, and it has hit a chord with a lot of parents. How do you know whom to trust, and how to protect your child?

The grand jury indictment in the Sandusky case might sounds unbelievable, but a psychologist who spoke with the FOX Medical Team who works with child sexual abuse victims says it happens more often than you'd think. Nancy McGarrah says it’s an issue parents can’t afford to ignore.

A lot of parents worry about strangers, but when it comes to sexual abuse, McGarrah says the bad guys often aren’t strangers at all.

"What's much more common is somebody that's a very trusted person to the child,” McGarrah explained. “It could be a family member, it could be a close person to the child, like a coach or instructor or a counselor, someone at their church."

And McGarrah says the abuse often starts with the predator "grooming" a child,

"And that's where they gain the child's trust and they become more and more intimate with the child," she said.

It may start out innocently,

"Taking the child to get ice cream or spending a little extra time at school with the child,” McGarrah said. “Giving special interest to that child."

"And then it may move to something like a backrub,” she added. “Something that is sort of invasive, but the child find it to be pleasurable. They're getting special attention."

But as a parent, how do you know? McGarrah says you should watch for a change in your child's behavior, like a kid who loves school but suddenly doesn't want go.

"For a younger child, they used to sleep through the night great, eat great, toileting issues were fine, and then something changes," she explained.

McGarrah says it's never too early to start protecting your child, and that means talking about what's private and what's not. Kids as young as 2 or 3 can understand certain areas of their bodies are "off limits."

“You can say, for example, ‘the part that's under a swimsuit,’ because it's not just genitals,” said McGarrah. “But that is their private area and other people just can't touch it."

We think of teenagers as more able to fend off abuse, but McGarrah says they need approval, and understanding, and that can make them vulnerable.

"I would worry about that if I had a child that was in that preteen or early teen years and somebody that was, say in their early 20s, was their best friend,” McGarrah said. “It may be innocent, but you kind of want your red flag to go up that point."

McGarrah says it's not unusual for boys to wait years before reporting sexual abuse, as with the alleged Penn State abuse. That may be because they may feel shame, especially if their abuser was a male. Often kids feel they must have done something to warrant the abuse, and that's not true.

For more stories from WAGA Atlanta go to myfoxatlanta.com.

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