William Alexander of Mariah Cunningham and two children

William B. Alexander, now 29, pleaded guilty to helping his half brother torture and kill a Little Rock mother and her two young children during a robbery that prosecutors said escalated into extreme violence.

The killings occurred in December 2017 inside an apartment at the Rosewood Apartments on Lancaster Road. The victims were Mariah Cunningham, 24, her 5-year-old daughter, A’Laylaih Fisher, and her 4-year-old son, Elijah Fisher. Investigators later determined the attack centered on an attempt to rob Cunningham’s home.

Prosecutors said Alexander restrained Cunningham while his half brother, Michael Ivory Collins, tortured the children in front of her in an effort to force her to surrender money they believed she had. Each victim suffered dozens of stab or slash wounds. All three died at the scene.

Police arrested Alexander in January 2018 after developing him as a suspect during the homicide investigation. A month later, authorities arrested Collins in Chicago and extradited him to Arkansas. Cunningham’s grandmother discovered the bodies after the children failed to arrive at school and she could not reach her granddaughter.

Alexander ultimately pleaded guilty to aggravated robbery and three counts of first-degree murder, avoiding a capital murder trial. A Pulaski County judge sentenced him to 60 years in prison. His half brother, Collins, went to trial and received life without parole after a jury convicted him of capital murder.

Court records show Alexander had prior felony convictions for forgery and theft before the killings, though none involved violent offenses. At the time of his plea, both brothers were also charged in a separate 2017 homicide involving the death of Billy Thornton, 64, at a Little Rock apartment complex. That case stemmed from a shooting initially reported as a possible suicide but later investigated as a homicide.

Alexander entered the Arkansas prison system in 2019. He has had more than 60 disciplinary actions, including multiple batteries, aggravated battery, threats, throwing things and sexual activity. He is serving his sentence at the Cummins Unit, with a projected earliest release date in 2061.