William Garriepy, 83, and his 9-year-old grandson, Lukas Pearson, died in a fire on the night of Jan. 28 at 885 Norwich Road, police said.
Autopsies were performed a day later and the Office of the Chief Medical Examiner determined that Garriepy and Pearson died of smoke inhalation and thermal injuries, police said.
The manner of death was certified as an accident due to a residential fire.