Authorities say the 4-year-old was starved, burned, tortured and forced into the freezing cold on the fire escape before he died. He weighed just 37 pounds, half the weight of a normal child his age.
The indictment against Kryzie King is sealed and it is not yet known if murder is one of the charges.
King is already charged with endangering the welfare of a child and assault.
The boy's 37-year-old father, Okee Wade, remains jailed on fraud charges in south Jersey, hopeful for release so he can bury the son he had sole custody of despite a long rap sheet. The judge is reportedly conflicted due to the fact that Wade has skipped court days in the past.
When he was arrested yet again in December, he handed the trusting boy to 27-year-old Kryzie King, described as a transgender performer.
Authorities say she burned the boy with cigarettes and a hot oven grill, and also put the near-naked child on the balcony for more than an hour the night before he was found dead in her bathtub.
He had also been whipped and cut, a cloth stuffed in his mouth when he cried.
Meanwhile, the boy's body was finally claimed on Wednesday evening, one week after his death.
As community activist Tony Herbert told Eyewitness News on Tuesday, the body was picked up by Sorrentino Funeral Service, having been released to his biological mother Ashlee Dobson. She was not there for the transfer.
Myls' wake and funeral services are scheduled for Tuesday at First Corinthian Baptist Church in Harlem. The wake will be from 4-7 p.m. and the funeral from 7-8 p.m.
The Reverend Al Sharpton will give the eulogy.
The funeral home is offering their services free of charge. The New York State Office of Victim Services, which helps crime victims in need, is giving the family $6,000 for the plot, casket, and burial costs.