Brother Stabs Sister He Believed Was Poisoning Him for Years in Kitchen, Then Finishes Her Food: Police

Dwayne Breis Robinson, 34, has been charged with first degree murder in the death of his sister Diane, 36, in the home they shared in Vancouver, Washington. It wasn't until days later that police became involved, when Diane's ex-husband called them, according to Law & Crime.

As detailed in a press release from the Clark County Sheriff's Office, deputies were dispatched to the residence on the night of September 18 after they were contacted by Diane's ex-husband Kenneth Leachman following his own visit to the Robinson's home.

According to the report, Leachman had dropped in to check on Diane "who had not been heard from in several days." He instead found Dwayne, per the release, who first told Leachman that he wasn't welcome at the house, per The Columbian.

When pressed about where his ex-wife was, Leachman told police Dwayne told him "that he had stabbed and killed Diane."

Dwayne was still at the home, per the sheriff's office, when deputies arrived and was detained. A search of the house revealed a dead female inside, per the document.

The body of Diane Robinson was reportedly still in the kitchen, but now under a blanket authorities believe was placed there intentionally by Dwayne, per Law & Crime.

When questioned for a possible motive for the alleged killing, Dwayne purportedly told authorities he suffered from "depression, sadness and pain" because he believed his sister had been poisoning him for several years, per court documents reviewed by the Oregonian.

He further allegedly told them that he stabbed his sister while she was eating, only to then finish her food himself, because he knew "it wasn't poisoned." Dwayne allegedly told authorities he'd grown tired of being poisoned, per The Seattle Medium, and so had been planning to kill her in the week before her death with a hunting knife.

Fox affiliate KPTV detailed previous convictions for Dwayne Robinson, including a 41-month sentence after he pled guilty to first-degree robbery in October 2019. In September 2019, he pled guilty to reckless endangering and attempt to elude charges, which gave him six months in jail.

A year prior to those charges, Robinson had pled guilty to harassment with death threats for a 2018 incident involving his parents, leading to a one-year-prison sentence.

The suspect is currently being held at the Clark County Jail. At a competency hearing earlier this month, a judge did not set bail, as reported by local NBC affiliate KGW, so he is set to remain behind bars until his next court appearance on October 9.