The Jennifer Hudson family murder trial began this week with the singer/actress as the first witness to take the stand. With no surviving witnesses to the murders, prosecutors must offer overwhelming circumstantial evidence that William Balfour, the ex-husband of Hudson’s sister Julia, committed the crime that occurred on Oct. 24, 2008.

They are expected to introduce evidence in the next few days that includes cell phone records and security-camera footage that place Balfour in the area of the killings, and will also try to tie Balfour to the alleged murder weapon, a silver and black .45-caliber handgun.

Hudson’s mother, Darnell Donerson, her 29-year-old brother Jason Hudson, and her 7-year-old nephew Julian King, were the victims of the vicious murders. Jennifer Hudson, who was in Florida at the time, had to fly into Chicago to identify the bodies of her mother and brother.

Originally, Hudson’s nephew was missing. Hudson offered a $100,000 reward for his safe return. Unfortunately, he was found dead days later in the back of a parked SUV. He died of a gunshot wound.

Public Defender Amy Thompson told jurors during her opening statement that DNA found on the gun did not match Balfour, which “absolutely, positively” excludes him as the killer. But prosecutors will try to prove that Balfour targeted the family as revenge towards Julia for their separation. Hudson claims that none of the family wanted Julia to marry Balfour because of the way he treated her, and that she was never friendly with him. Julia claims that Balfour told her that he would kill her family. “If you leave me you’ll be the last to die. I’ll kill your family first,” she quoted him as saying.

While on the stand Hudson spoke about her family while fighting back tears, and although emotionally taxing, vowed to be in attendance every day of the trial. She also spoke about how she supported the family financially to quell the defense’s argument that Hudson’s brother Jason was a drug dealer and it was likely his involvement in the drug game that bought this unfortunate situation to his family’s doorstep.

The case is expected to continue for the next two to three weeks.