San Jose police on the scene of a fatal police shooting of a man suspected in a double homicide on May 3, 2017. (CBS)

SAN JOSE (KPIX 5) — A man bent on revenge killed his ex-girlfriend’s parents in their San Jose home.

We’re digging deeper into the troubled relationship that ended in a horrific double homicide in San Jose’s Willow Glen neighborhood.

Police have confirmed that Rachel Prabhu had recently taken out a restraining order against her ex-boyfriend Mirza Tatlic when their relationship became abusive.

Read Also: Jilted Boyfriend Goes On Killing Spree, Fatally Shot By Police

But one domestic violence expert says restraining orders can backfire.

Colsaria Henderson with Next Door Solutions to Domestic Violence said, “For some survivors and some situations, restraining orders actually incite more violence.”

Henderson says her agency informs victims about the pros and cons of restraining orders, but doesn’t necessarily recommend them.

“Restraining orders can escalate the situation for some abusers, make them more violent,” Henderson said. “They get very upset when you involve law enforcement or the criminal justice system.”

No one knows if that’s what happened with Mirza Tatlic, who ambushed the Prabhu family as a way of getting back at his ex.

Her father Narem Prabhu — the VP of Engineering at Juniper Networks — was shot in the doorway of the family home on Laura Ville Lane Wednesday night.

His wife Raynah Prabhu was also shot and killed, and their 13-year-old son was held hostage, before a police sharpshooter killed Tatlic, who raised his gun at officers.

Tatlic graduated in 2010 from Prospect High School in Saratoga where he played football and basketball and went on to college in San Diego.

A former roommate says he was inventive and wanted to start up businesses.

But police say he had mental problems.

Instagram posts directed at Rachel Prabhu became ominous. In one, he says “the devil smiles but the eyes sell the evil.”

On April 25, Tatlic wrote there would be “no mercy on the ones that love you most.”

A final post shows a pack of cigarettes and the words “hope I get more than just one…the real Mirza…sucks this cost me my lyf.”