A Chicago jury has found the brother-in-law of actress Jennifer Hudson guilty of all charges of killing her mother, brother and young nephew.
William Balfour, the estranged husband of Ms Hudson's sister Julia, was charged with killing his in-laws and hiding his stepson's body.
Julia Hudson found the bodies of her mother, Darnell Donerson, 57, and brother, Jason Hudson, 29, in their family home in October 2008.
The body of her seven-year-old son Julian King was discovered three days later in a stolen sport utility vehicle.
"This defendant was fuelled by his obsession, his jealousy," assistant state's attorney Jennifer Bagby told jurors as the prosecution wrapped up the case earlier this week.
"He told her again and again: If you leave me, I'll kill you. I'll kill your family first. You'll be the last to die."
Ms Hudson has attended the entire trial, which opened a window onto the troubled Englewood neighbourhood where Ms Hudson was raised and which her family never left.
She had testified in April how no one in her family wanted her sister to marry Balfour.
"We didn't like the way he treated her, and I didn't like the way he treated my nephew," the 30-year-old singer and actress told the Chicago court.
In a statement issued after the verdict was announced, Jennifer and Julia Hudson said the entire family was relieved and grateful.
Public defender Amy Thompson - who insisted at the trial that police rushed to judgement and failed to look into Jason Hudson's drug connections - said she planned to appeal the verdict.
"William Balfour is innocent of these murders and we're hopeful that the appeals court will look at this with a very careful eye," Ms Thompson told reporters.
"My client is a very stoic young man," she added. "He doesn't emote much. He's hopeful in the appeal. This was a very hard blow for him."
Balfour faces a mandatory minimum sentence of life in prison.
