ALLENTOWN — The death of a 3-year-old Allentown girl who fell from a fourth-story window along with her 5-year-old sister last year has prompted a wrongful death lawsuit.

Jessica Tatum, the mother of Tamara and Tiana Arnette, is suing the owners of the apartment building at 702 Turner St., which houses once-homeless families pursuing educational or vocational training. Tamara died shortly after falling 42 feet to the sidewalk below on June 5, 2015. Tiana, then 5, was seriously injured.

The suit, filed this week in Lehigh County Court, alleges that the owners were negligent for failing to properly secure the apartment’s windows, even though they knew young children were living there. Although there were locks on the windows that prevented residents from opening the windows more than a few inches, the lawsuit alleges that the owners knew that residents often removed these locks because the apartments did not have air conditioning.

“It was the responsibility and duty of the defendants to undertake the necessary steps to make these apartments safe for the tenants and their children,” the suit states. “It was foreseeable that such children would be most likely to fall from a fully opened window to the sidewalk below.”

The building is part of the Transitional Housing Program for the Community Action Committee of the Lehigh Valley and is owned by Valley Housing Development Corp., a nonprofit affordable housing group that is based in Emmaus and contracts with the Lehigh County Housing Authority for staffing and operational support.

Valley Housing Executive Director Daniel Beers declined to comment on the suit Thursday. But shortly after the incident, the organization announced that it was installing steel window gates on the more than 200 apartment units in 15 buildings that it and the Lehigh County Housing Authority own across the Lehigh Valley.

The family’s attorney, Joseph P. Lenehan, said the improvements came too late for his clients.

“We believe this should have been done before, and that it was feasible for them to do it,” Lenehan said.

The girls fell just before 8 p.m. According to the lawsuit, Tatum was in the apartment and had stepped into another room when she heard “what sounded like a screen giving way (or popping) followed by a scream.”

She rushed into the room and discovered that her daughters had fallen, the suit states. Witnesses told police that they saw the children sitting in the window and waving to people below shortly before they fell.

The children were rushed to Lehigh Valley Hospital -Cedar Crest, where Tamara was pronounced dead from blunt force trauma. Tiana sustained numerous injuries, including a broken pelvis and concussion. Lenehan said Thursday that she’s still healing.

“I am happy to report that she seems to be doing better, though I cannot say that she has fully recovered,” he said.

Tatum’s mother, Constantia A. Simmons, is also named as a plaintiff in the lawsuit. They are seeking a jury trial and damages in excess of $50,000.

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