How about lots of photos of them in their various stages of life? Infant, youth, young adult, wedding, with their children, and in old age. Perhaps one of the photos would show them doing what they loved (cooking, gardening, golfing, or such). Any humorous incidents that you can remember? Or generous, loving ones? How did they interact with each other? You are lucky in that you can convey first-hand information that will add color to their profiles (but still try to maintain the third person voice).