Cooper Harris died on July 18 ; his death was consistent with hyperthermia or overheating . Police have charged his father , John Ross Harris , with murder . Court documents state he caused child deaths in cars . Harris spoke to the crowd at Cooper 's funeral , via speakerphone .
Cooper Harris died on June 18 ; his death was consistent with hyperthermia or overheating . Police have charged his father , Justin Ross Harris , with murder . Court documents state Harris researched child deaths in cars . Harris spoke to the crowd at Cooper 's funeral , via speakerphone .