A police car sat outside at Dean Drive in McLean as red crime tape kept people away from the home where a murder suicide happened on Friday.

Detectives worked through the night and discovered Helen Hargan, 23, killed her 63-year-old mother -- Pamela Hargan – before turning the gun on herself.

However, police haven't said what led up to the violence.

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A neighbor asked, “Did the daughter come in with the gun? Is that the daughter's car? Where is she from? When did she get here?”

They were questions people were still waiting to hear from police about.

Pamela Hargan moved into the home with her oldest daughter and grandchild about two years ago.

The little girl was not inside of the house when the shooting happened.

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“They're your neighbors even though you don't really know them,” the unidentified neighbor said.

People who live in the area said they have to do a better job of checking on one another and catching signs that may prevent something like this from happening again.

“Too many moving parts and none of us know because we're all insular and isolated,” the neighbor said. “We're all kind to one another but we don't bother each other.”

Both of the Hargan's bodies were taken to the medical examiner's office for an exact cause of death.