By Amanda Porterfield

WEST ALLIS, Wis. (CBS58) -- A West Allis teenager went to a sleep over and never came home.

Emma Lorenz didn't get to live a full life.

Her parents, Julie and Steve Lorenz, say at 18 was still searching for a best friend.

Kendall Marinier was a friend of a friend on Facebook.

Emma decided to meet in her real life and the two became best friends.

A nervous feeling stayed with her parents until the day their daughter died.

"When she asked to spend the night at Kendall's house, the strangest thing for me is I just started bawling and I said no you can't. And I never do that," Julie said.

But she changed her mind.

Emma was supposed to be home by noon the next day.

"She wasn't answering me and that's very unusual. I was completely panicked I went and found her iPad and did find her iPhone. That led me to 6th and State," Julie said.

Julie found out her daughter overdosed on heroin at Kendall's house.

She died in her sleep.

"I mean 12 days she knew this girl. Emma wasn't doing anything prior to those 12 days," said Julie.

Julie says she always checked out Emma's friends, but she didn't look up Kendall's criminal record because the girl was only 17.

"Unfortunately once Emma had passed, then I CCapped her and sure enough she had been arrested for armed robbery possession," said Julie.

Dr. Paul Krepel, a child and family therapist, says kids of all ages are more vulnerable at someone else's house.

"You notice whose house they choose to be at then you should be asking questions because they're making that choice based on something. Always listen to your intuition," said Dr. Krepel.

"I thought okay this is what she wants I am not going to stop her. And obviously I wish I did," Julie said.

"I would have never let her out of that truck that day," Steve said.

Kendall admitted to having a heroin addiction. She faces charges of intent to distribute and bail jumping.

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