The victims, 44-year-old David Sherrod, 51-year-old Alma Cox-Sherrod and 7-year-old Jaquan Cox, were found inside the Lafayette Avenue apartment around 3:30 a.m. All three were pronounced dead at the scene.
The child is believed to be the dead couple's grandson.
Neighbors complained about the smell coming from the second-floor apartment. They say the family recently moved into the building and may have worked for the management company, collecting rent or possibly working as a porter.
Police believed the deaths to be the result of a double murder suicide, and the bodies may have been in the apartment since the weekend.
No arrests were immediately made.
Authorities said David Sherrod had a criminal record and served time in prison from 1998 to 2008.
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