EMINGTON, Ill. (CBS) — Authorities say they may never know why a woman in a rural Illinois town shot each of her three children and her live-in boyfriend before killing herself.

As WBBM Newsradio’s Lisa Fielding reports, Livingston County Chief Deputy Sheriff Marvin Rutledge says the investigation has stalled into the murder-suicide Friday.

LISTEN: WBBM Newsradio’s Lisa Fielding reports

Investigators say they know Sara McMeen, 30, shot and killed her boyfriend, Daniel Warren, 29, and her own three children – Skyler Lemke, 8, Ian Lemke, 7, and Maggie Warren, 10 months, with a semi-automatic handgun.

But Rutledge says he is not sure authorities will ever know the motive. McMeen is not around to ask what happened, as she turned the gun on herself.

Investigators plan to talk more to family members and friends after funeral services this week.

This past Friday, authorities found all five bodies when they arrived at the home in Emington, a 117-person town about 85 miles southwest of Chicago.

Autopsy results released Monday show that all five family members died of gunshot wounds. Sara McMeen died from a single gunshot wound to her neck. Her hands were stained by soot, and a semi-automatic handgun was found next to her hand, authorities said.

Daniel Warren, who was found inside the house, died of gunshots to his back and neck. The three children and McMeen were found outside. Skyler Lemke was found shot three times. Ian Lemke had one gunshot wound. Maggie Warren, the 10-month-old, died of gunshot wounds to the head, authorities said.

The gunfire started minutes after Skyler and Ian Lemke arrived home from school on the last day before Christmas break. One neighbor said he could hear two rounds of gunshots from inside his home one street away.

When she heard the first shots, Annelise Fiedler ran out of her home to check on what the noise was. She told The Associated Press on Saturday that she could see McMeen hovering over her baby as if she had dropped her.

Fiedler asked McMeen if everything was all right.

“She looked at me and said, `No, everything is not all right,”‘ Fiedler said. Then, Fiedler said, McMeen shot the baby.

Memorial funds have been set up in the names of the three children at the First National Bank in Dwight, Ill.

Donations can be mailed to the bank at P.O. Box 10, Dwight, Ill., 60420 in care of Ian Lemke, Skyler Lemke or Maggie Warren.

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