Robert Davis Bever, 18, and Michael John Bever, 16, were each charged with five counts of first degree murder in the July 22 deaths of parents David Bever, 52, and April Bever, 44, and siblings Daniel Bever, 12; Christopher Bever, 7; and Victoria Bever, 5.

The brothers were also charged with one count of assault and battery with intent to kill involving multiple stabbings inflicted on a 13-year-old sister who survived the attack.

Robert and Michael Bever are scheduled to make an initial appearance on the charges in Tulsa County District Court Monday, when a plea is likely to be entered on their behalf and a preliminary hearing date set. Court records did not show whether the brothers are represented by an attorney.

Tulsa County District Attorney Steve Kunzweiler, whose office filed the charges, has said Michael Bever will be tried as an adult.

First-degree murder is punishable by life in prison or death, but Kunzweiler has said the maximum sentence facing the younger brother if he is convicted of first-degree murder is life in prison or life in prison without the possibility of parole. While the death penalty is legal in Oklahoma, the U.S. Supreme Court in 2005 banned the execution of anyone under the age of 18 at the time a crime was committed.

Officers responding to a 911 call placed from inside an upscale home in the Tulsa suburb of Broken Arrow found blood on the front porch and heard a voice inside crying out for help, authorities said. Officers entered the residence and found the 13-year-old girl lying on the floor with multiple stab wounds.

The assault charge alleges that the brothers used a knife to stab the girl "multiple times with such force that was likely to produce death."

The girl, according to Robert Bever's arrest report, named Robert and Michael Bever as the people who attacked her and the rest of her family. A 2-year-old girl was found unharmed in an upstairs bedroom and has since been placed with relatives after initially being taken into state custody.

A police dog tracked the two teens into a wooded area behind the family's home shortly after officers arrived on the scene, and two knives and a small hatchet were discovered inside the home, police said.

Broken Arrow officials have said they will release a recording of the 911 call on Tuesday. Broken Arrow Police Sgt. Thomas Cooper, who has described the call as "gruesome," said authorities believe it was made by one of the boys just before he was killed.

Cooper said the caller reports that a brother is attacking the family before the caller and dispatcher have a short exchange about the location of the home.

Broken Arrow, a suburb of about 100,000 people, is on the Arkansas River just southeast of Tulsa and the home is in a well-established, upper-middle-class neighborhood surrounded on three sides by a country club. Property records showed the home sold for $245,000 in 2007, and Tulsa County tax records show it is among the largest and most expensive homes on the block.