A view of the third-floor porch on the 8200 block of South Maryland Street Monday morning, where one-month old Jeremiah Range fell to his death. (Heather Charles/Chicago Tribune)

A view of the third-floor porch on the 8200 block of South Maryland Street Monday morning, where one-month old Jeremiah Range fell to his death. (Heather Charles/Chicago Tribune)

(WGN-AM)- The tension between the young couple had flared to a physical confrontation before, and police had been called and reports filed.

This time, on a third-floor back porch, there was a month-old baby in the middle of it all.

And when it was finished, the baby, Jeremiah Range, had sailed off the porch and onto the ground below, suffering fatal injuries, authorities said. He was transported to University of Chicago Comer Children's Hospital.

Detectives were still trying to sort out the melee, which involved several people, including one who was reportedly stabbed. A determination of the cause of death is pending police investigation, according to the Cook County medical examiner's office.

According to preliminary police reports that remain under investigation, Jeremiah was being carried unsecured in a car seat by his mother before he plummeted from the porch in the 8200 block of South Maryland Avenue just before midnight Sunday.

The 20-year-old mother had come to the home of her estranged husband to pick up Jeremiah who was there with his brother, 5, and sister, 1 1/2, friends said. The mother arrived with two other men, and a quarrel broke out, the preliminary reports said. At some point, the husband, also 20, kicked his wife, jarring the carrier and sending Jeremiah over the railing, the reports said.

The backyard of the home was quiet Monday afternoon. A child's toy truck and a deflated ball rested at the bottom of the porch steps.

No charges had been filed as of 9:45 p.m., said Calumet Area Sgt. James Baker. The case was considered a death investigation, and it hadn't been determined whether a crime was committed, Baker said.

A source close to the investigation said the incident was related to ongoing domestic trouble between the estranged couple.

The two had known each other since the 2nd grade and reunited in high school, when they had their first child, said Nicollette Allen, the mother's friend. They married at City Hall in 2007, Allen said.

But the relationship turned violent, according to Allen and court records.

The husband was charged with domestic battery in 2008 after he allegedly threatened his wife with a knife and dragged her by her hair onto a South Side street, according to the court records. The charges were later dropped, however.

Allen said her friend had started a new relationship with another man and that he was one of the men with her Sunday evening.

Allen said there had been a party at the husband's house for the estranged couple's 5-year-old son, and her friend decided to leave all three of her children there.

The second man who accompanied the mother called Allen to tell her what happened, saying that he'd been stabbed, she said.

Allen, who is expecting her own child, said of her friend: "She was so excited. Our babies were going to be a few months apart. They were going to grow up together."

(The Chicago Tribune contributed to this story)

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