This might be an odd question. My mom does walking exercises and aerobic videos and some very light weights (5lb). She knows that I make protein shakes (with spinach, berries, flax seed) after my workouts. Is whey protein recommended for elderly people (she's 62) too?
Yes, whey protein can be helpful for elderly people also. The Journal of The American College of Nutrition, JACN, reports that the elderly have greater protein requirements than younger adults. Given that your mother is exercising, ingesting whey protein (or other biologic sources of protein), especially immediately following exercise, may well help her minimize age related muscle wasting. Here are some references:
According to a study in the January 2008 issue of "Current Opinion in Clinical Nutrition and Metabolic Care",
Even though your mother's exercises may not be very intense, it sounds like she is on the right track and the addition of whey protein following her exercises can help maintain muscle mass and should not hurt (unless she has kidney disease as @Evain Plaice pointed out).