Adonis Jarvis was pronounced dead at a hospital in the Bronx on March 19.
Officers were called to the hospital after he appeared to be malnourished and the Medical Examiner ruled his death a homicide.
On Thursday, his mother and grandmother, 36-year-old Geneva Jarvis and 62-year-old Denise Jarvis, were arrested on murder charges.
Officials say an autopsy revealed that the teenager was starved to death.
It also appears that the teen's twin brother was also hospitalized for starvation but survived.
Both children were described by law enforcement as nonverbal.
Police say they both exhibited signs of chronic neglect, starvation and dehydration upon arrival at the hospital and they had sores on their legs and all over their bodies.
Both women are scheduled to appear in court later Thursday afternoon. They are also facing a slew of charges in connection to the victim's sibling.
This story will be updated as more information becomes available.
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