Deputies said the 9-year-old was taken to the hospital after being hit while riding an electric dirt bike on Thursday.
Police said the man was riding a bicycle on Quitman Street when he was hit by a driver who did not stop to render aid.
Deputies said the man was hit first by a driver who stopped, but when his girlfriend rushed to help him, another car hit her and took off. The two cyclists both died from their injuries.
Officials said the off-duty officer was riding his bike in Katy before being hit by a driver in a U-Haul truck, who was charged with intoxication manslaughter.
The Harris County Sheriff's Office said the ambulance had a green light when a cyclist, who was in the crosswalk without the right of way, struck the vehicle.
Some cyclists lay on the ground pretending to be deceased to show how they feel the City's latest decision to remove the bike lane protections will impact public safety.