other vague double vision swollen prostate gland weird sleeping habits

My old mother and father (age 86) HEALTH, STRENGTH, ENERGY, POSITIVITY, OPTIMISM, LONGEVITY, VITALITY, SOUND MIND (no dementia, confusion, childishness, arrogance, stubborness...). My father - 86 - skin tumors, one eye almost blind, the other vague/double vision, swollen prostate gland, weird...