There are some 90 year olds that are more capable than 70 year olds, it depends on the individual. My father in law is 89 and very sharp. When I visited him in Mar, he brought out a 1939 Police Special that was his dad's service weapon. He kept this gun loaded in his bedroom for self defense. I asked when the last time he fired it and he couldn't recall so we went to the range. He couldn't hit a target at 5 yards and had difficulty pulling with the trigger when using double action. We had fun, he shot his dad's gun but when we got home, I recommended that he not keep this gun loaded because I feared he hurt himself or his wife. I would never suggest that he CC. There were other very elderly folks at the range that were having no problems, so it's not age that matters, but the capability of the person. I agree with the others that you take him out to shoot to see how he does.