Singleton, 27, was picked up by Phoenix police at his mother's home on October 21 on a bench warrant, after his failure to appear for a court date related to possession of meth, heroin, and drug paraphernalia. He also faced two previous felony charges for unlawful entry.
That was the last time she saw her son alive. On November 5, two plainclothes detectives with the MCSO's jail crimes unit came to her home to tell her that her son had been found dead in his cell the day before.
"They said they found him in the praying position at his bed, non-responsive," Kramer told New Times.
She says the detectives explained that during her son's brief stay in jail, he had been "complaining of stomachache," had "blood in his stool," and had to visit the hospital twice.
"I was mad, screaming," remembered Kramer. "I couldn't believe it."
MCSO spokesman Chris Hegstrom confirmed that Singleton died November 4, but otherwise could offer no details about the prisoner's demise.
"The case remains under investigation," Hegstrom stated via e-mail, "and is awaiting the Maricopa County Medical Examiner’s report."
Kramer's sister, Sandra La Freniere, tells New Times that she was with her sister when the MCSO detectives stopped by. They said Singleton had been involved in an altercation with a detention officer, she said.
As a result, Singleton had been transferred from general population at Durango jail to solitary confinement in Fourth Avenue's Special Management Unit, the detectives told them.
Both women said Singleton had struggled with drug addiction but that he wanted to kick the habit.
"He was on heroin," admitted La Freniere. "He wasn't the same as he used to be. The drugs took a toll on him. But he was trying to get clean."
Kramer says her son never wanted to do heroin again. He knew he would be going back into jail and planned to kick there.
"I knew he was going to be hurting," she said. "I just didn't know he was going to end up dead."
The U.S. National Library of Medicine notes that "abdominal cramping" can be a symptom of withdrawal from opiates such as heroin.
However the same source notes: "Withdrawal from opiates is painful but usually not life-threatening.."
Kramer also says she is concerned about abrasions on Singleton's head, as can be seen in a mortuary shot she provided to New Times.
While Kramer waits for answers, she's had to tell Singleton's children (ages 3, 6, and 8) that their father is not coming home.
She's also struggling to pay for burial expenses and is trying to raise money through a GoFundMe account to pay for a headstone for her son.
Singleton would have been 28 on February 11.