Crime Alert, I'm Nancy Grace, breaking crime news now.

Ethan and Savannah Cats ask a close friend, Nicole Verzi, to babysit Leon and Ari,

their six-week-old twins, just for the day while they catch up on sleep.

After several hours with the boys, the babysitter rushes the two to the hospital.

Nicole Verzi claims Leon fell from his bouncer chair while she was preparing a bottle.

The baby has a skull fracture and multiple brain bleeds.

Leon dies.

Doctors say there's no way Leon's injuries were an accident.

Ari also shows signs of abuse.

Nancy Vierzy is a fifth year PhD student studying depression's effects on human behavior

and physical health.

Vierzy's lawyer describes her as a longtime family friend of the Katz's, adding that his client is backed by a quote, loving and supportive family.

Vierzy is now held at the Allegheny County Jail.

Nicole Aversy, 29, pleads not guilty to homicide, ag assault, and endangering welfare of children.

Samera Thomas 18 chats online with a

date for about a week before they decide to meet in person.

As the date walks up the front drive, she suddenly gets cold feet.

But instead of cancelling, she calls 911, telling the operator her, quote, abusive ex-boyfriend

refuses to leave and is threatening to hurt her.

Iowa cops meet the confused man as he's leaving Thomas's front yard.

He shows them the messages between the two to prove he's never even met Sumaya Thomas.

Officers turn their attention to the teen girl.

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