My sister is living with my parents, dad:90 mother:89.  Every summer they drive 2 days to a family summer cottage.  Last year, my dad promised to let someone drive them this summer.  Now he is determined to drive himself again.  He does okay driving in his local community where he is familiar with roads, but out of town, he can be hesitent about the direction, gets sleepy, sometimes doesn't focus on cars around him, and is distracted because he is pointing out things he sees or talks about what's on his mind. He has always been determined to do things his way, and he of course doesn't want to give up his independence, but for his safety and the safety of others, it just isn't reasonable for a 90 year old to be driving on a 2 day trip that involves multiple expressways and even driving in some cities.  My sister has gently tried to have a reasonable conversation with  him, but it just escalated very quickly as he is immediately on the defense.  She has consulted an aging expert who made a possible suggestion that my sister go along and 'share' the driving.. letting my father drive the less difficult areas, but to be honest, the whole stretch is diffficult as it is out of town, etc.   And then the fact that my sister would have to take off work, fly back home, and then the issue about how will they get back.. she would have to repeat the process..  I have downloaded AAA quizes, information about elderly driving, and other resources.  But we are looking for more advice as to how to handle this determined, intelligent, aging man.  Thank you.