An elementary school student is credited with helping save a friend after 18 months of sexual abuse by a family friend.

That friend, Andrew Cook, 30, was sentenced this month to 21 years in prison after pleading guilty to sexual conduct with a minor and sexual exploitation of a minor.

On October 27, 2017, Peoria police were contacted by an elementary school who alerted them that one of their students may be the victim of sexual abuse.

The school was contacted by a parent who told them that the victim confided in their child that she was being tied up, sexually abused and photographed. She was also threatened by the suspect with death if she exposed him.

The victim also told her friend that the suspect had broken her arm. School officials confirmed that the victim came to school in a sling at the beginning of the school year.

Police and investigators from the office of child welfare removed the child from the Peoria home and interviewed her.

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The victim recalled multiple incidents over the past 18 months of sexual contact and the taking of sexually explicit photos. She identified the suspect as Andrew Cook, a family acquaintance.

Police collected Cook’s cell phone memory card. On it, they found multiple nude photos of the victim and Cook. In one of the images, a tattooed "W" is reportedly seen on a man's finger. Cook has the same tattoo on his finger.

Cook was arrested at his home last October.