The child's mother is now being charged with his murder. Jonathan Oakley was one of three children investigators say were being abused at the home in Hartford, but died from his injuries in October.
State Police say Jonathan, and his siblings, ages three and five, were being watched by their mother's boyfriend when the alleged abuse occured.
A Grand Jury handed down additional charges Thursday for Nathaniel Tucker and the child's mother, Samantha Oakley.
Oakley was initially charged with criminal abuse, but because authorities think she knew about the abuse, the jury indicted her for murder.
Tucker is also charged with murder, as well as being a "persistent felony offender."