M.W.
Hi M.,
My name is M. and I'm a Child Passenger Safety Instructor. Best practice is to leave your son rear-facing unilt about 18 months. This allows your son's head, neck and spine to mature, because his head is about 1/3 of his body mass. When your baby is riding rear-facing all of the crash forces are absorbed by the back of his carseat unlike forward-facing it is the harness straps. The straps are designed to stretch during a crash to help ride down the crash forces, which means his upper body comes forward. We worry with babies head weight the potential to stretch the spinal cord is greater which can call permament damage. You try letting him ride rear-facing for a little longer to allow those body parts to mature. Also, from my experience they nap better because they are reclined...forward-facing they are completely upright and have are harder time napping.
SAHM of a 7 month old baby boy.