CHICAGO (CBS) — There’s a growing type of identity theft most parents don’t know about.

As CBS 2’s Kate Sullivan reports, thieves are stealing children’s identities, running up bills and destroying the child’s credit. It often goes undetected for years.

Lots of us would love to own a $40,000 boat. Zach Friesen owned one when he was only 7 years old – but the problem was, it wasn’t the real Zach Friesen.

“When I was 17, I was in for my first job and was applying to schools – for universities – was denied student loans, denied a job,” Friesen said, “and found out that it was, in fact, for a $40,000 house boat in my name.”

One reason thieves are targeting children is that the threat is not on most parents’ radar.

“If a parent doesn’t know the signs to look for, they could be seniors in high school, seniors in college before they find they have thousands in debt,” said Becky Maier of the Better Business Bureau.

Maier says thieves are selling Social Security numbers that have no credit history attached to them. She found one selling for $800.

“It is a Social Security number that’s registered with somebody, but it’s not registered with the credit bureaus,” Maier said.

So how do thieves get the numbers? In Friesen’s case, police believe someone got his information from a pediatrician’s office.

Experts say you should avoid giving out your child’s Social Security numbers.

“If you can get away with not giving it away, that’s the best way to do it,” Maier said.

If you’re getting calls for your child from telemarketers, or getting credit card offers for them, consider that a red flag that something is up.

You can check to see if your child has a credit report by writing to the three credit reporting agencies – Experian, Equifax and TransUnion.

Friesen says it has been an ordeal to sort out.

“My credit score is very, very bad, as you can imagine $40,000 in debt over the course of 10 years could do,” Friesen said. “Now, when I cleared my name, that didn’t clear the negative score that I got.”

Finally, if you realize your child is a victim, call police and the Federal Trade Commission. Unfortunately, the thieves that stole Friesen’s identity were never caught because so many years went by.

Click here for information on how to protect your children from identity theft.

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