The Vermont son accused of murdering his family, including his politician dad, had "always shown an interest in death," his sister told detectives.
Brian Crossman Jr., 22, is accused of three counts of aggravated murder in the deaths of his father Brian Crossman Sr., 46; stepmom Erica Crossman, 41; and step brother Colin Taft, 13.
He has not yet entered a plea.
Crossman Jr. was visiting from his hometown of Granville, New York, when he allegedly shot his family to death in their Pawlet, Vermont, residence, last month, according to authorities.
During police interviews, Crossman Jr.'s 21-year-old sister, Rachael Crossman, said he had always expressed aggressive behaviors growing up.
She recalled an incident where he sat on their porch in Granville, "would make a gun gesture with his hand, point at passing cars, and yell 'Bang!' while pretending to shoot the passing cars," the arrest warrant obtained by the Lawyer Herald read.
Rachael said her brother had "always shown an interest in death" and that he had "tortured frogs and kittens in the past."
"She also recalled a separate incident in which he contacted family members and alerted them to a death within the family. When family members arrived at the residence to grieve, he told them he was only joking, and the event did not actually happen," the warrant stated.
In the years leading up to the purported killings, Crossman Jr. and his father were said to have a troubled relationship due to the younger Crossman's "mental health and learning disability," according to the warrant.
Loved ones said Crossman Jr. possibly suffered from schizophrenia and dissociative identity disorder, putting a strain between the father and son, the documents state. He sought treatment from several psychiatric doctors throughout the years and lived with his mother, who was out of town with her husband at the time of the alleged murders.
Authorities alleged mounting evidence, including bloodied clothing and cell phone records, tied Crossman Jr. to the killings and he was arrested in Granville.
On Thursday, he waived his right to extradition. He awaits transfer to Vermont to face the charges.
