Kaboni ordered a firebombing from prison that torched a home in North Philadelphia, and Kidada, 31, helped plot the arson that killed six members of an informant's family, a trial found.
She was convicted in May of six counts of murder in aid of racketeering, retaliating a witness and related offenses.
She faced a mandatory sentence of life in prison plus 10 years.
U.S. District Judge Barclay Surrick imposed the sentence on Friday and delayed the sentencing.
"I have not heard any remorse from you," he said.
Savage had earlier claimed that she had nothing to do with the killings.
"Your honor, I was railroaded," she said. "The system is unjust. I would never hurt anybody regardless of that guilt verdict. I know I did nothing wrong."
Kidada had contacted her older sister Conchetta Savage to find a new lawyer, the Philadelphia Daily News reported.
Assistant U.S. Attorney David Troyer told the judge that Kidada was attempting to manipulate the system by delaying her sentence.