once a man, twice a child

When one reaches very old age, one's mental or physical capacity is often reduced to that of a child, as due to disease or senility. Derived from a line in William Shakespeare's Hamlet: "An old man is twice a child." After my grandfather suffered his second stroke and struggled mightily with basic things like eating and talking, I found myself often thinking of the adage, "Once a man, twice a child." A: "I promised my mother that I would take care of her if the dementia progressed too far." B: "Once a man, twice a child, as the bard says."