(EVERGREEN TOWNSHIP) -- Three people were injured after a vehicle ran into the back of a silage wagon being pulled by a John Deere farm tractor along West Deckerville Road near Germania Road Christmas Day. Sanilac County Sheriff's deputies say the crash took place shortly before 7 p.m. in Evergreen Township. An investigation showed that the vehicle driven by 66-year old Michael Fox of Caro was traveling west on Deckerville Road when he ran into the back of the unlit wagon. The tractor was driven by 44-year old Dennis Hyatt of Columbiaville. Fox and his wife were transported to Hills and Dales Hospital in Cass City with non-life threatening injuries. Their 13-year old son was a rear seat passenger in the vehicle and was not wearing a seat belt at the time of the crash. He suffered serious head trauma and was transferred from Hills and Dales Hospital by Life Net to Covenant Medical Center in Saginaw where he is listed in stable condition. The driver of the tractor was not injured. Deputies say alcohol was not a factor in the crash, which remains under investigation. The Argyle Fire Department assisted at the scene.