Sorry to hear of your plight,ultimately you may have to step on your faher in laws toes.I have 4 grands,and occasionally my kids need to interveen for both the safety of me and my grands.There is no text book answer to your problem,but I believe that being straight forward with your father in law is necessary,and tell them you are concerned for him and them.
As for his driving if youfeel that strongly about
his ability to drive you should contact your state motor vehicle department,and let them make a determination.I wish you all the best.
Ed-Diagnosed with Parkinson's Disease in 1998.As long as I can fish life is good.Keep a great attitude.It benefits all.
support Healing Well thru the sponsors and with donations.The light is always on stay well,and listen to your neurologist.