From the stand, Nixon-James stared down at Khalil's parents - her cousin Floyd Wimes, 50, and his wife, Tina Cuffie, 45, on trial for allegedly starving and beating Khalil to death in March 2012. Child welfare officials and a judge plucked the boy from Nixon-James' safe care in 2009 and sent him back to Wimes and Cuffie even though the city had removed seven other children from their care for neglect.
On the night of his death, Khalil weighed 29 pounds when Cuffie and Wimes took his lifeless body to Children's Hospital of Philadelphia.
"Very emaciated, with scars everywhere," Kiwan DaCosta, a Children's Hospital social worker, testified Thursday about Khalil's condition at the hospital. "He didn't look like a 6-year-old. He looked 3. He looked like he was sleeping when I saw him. I just remember he had bruises everywhere."
On the stand, Nixon-James talked about the exceptionally good baby she called "Lil Lil," a child who learned to crawl and walk and recite his numbers and letters early.
First Assistant District Attorney Edward McCann, who is prosecuting the case against Wimes and Cuffie, displayed photos of Khalil taken when he was in the care of Nixon-James and of his foster grandmother, La Reine Nixon.
A chubby-cheeked Khalil smiles atop a rocking horse on his second birthday, wearing the tan dress pants Nixon-James had worried wouldn't fit over his belly.
Then one of Khalil laughing, weeks before the city sent him to his parents.
"I didn't want him to go, and he didn't want to go," Nixon-James said through tears.
On Wednesday, a medical examiner testified that from all the scarring, it was likely Khalil endured months of regular beatings with belts and cords. Two of Khalil's adult siblings said Wimes and Cuffie often kept him locked in an empty bedroom without food.
On Thursday, Homicide Detective Howard Peterman read aloud Cuffie's confession. That final morning, when Khalil was so weak he could barely stand, she said she "popped" him in the back of his head as he dried himself after a bath.
"He didn't even try to stop his fall," she told police. He was bleeding from his lip and had tried to crawl into bed but couldn't, so he lay on the floor. He was dazed and disoriented.
"Like he was looking right through me," Cuffie said.
But Wimes and Cuffie didn't seek help for Khalil. Instead, Wimes played the video game Call of Duty. Cuffie went to Popeye's. It was way too late, all those hours later, when Khalil's older brother finally yelled at his parents to take the child to the hospital.
A judge will decide as early as Friday whether Wimes and Cuffie should spend the rest of their lives in jail.
When Nixon-James was on the stand Thursday, she stared at Wimes and Cuffie.
They kept their heads down.