When King Lear introduces his plans to divide his kingdom among his three daughters, he begins with the following words:
Know that we have divided
In three our kingdom: and 'tis our fast intent
To shake all cares and business from our age;
Conferring them on younger strengths, while we
Unburthened crawl toward death.
In saying that he intends to "crawl toward death," he is showing that he intends to "shake all cares and business from his age" immediately but that he is not in any hurry to die. He is undoubtedly looking forward to another twenty years or so during which he can indulge in hunting, feasting, and merrymaking at the homes of his daughters. For their part, Goneril and Regan would prefer to see the old man die as soon as possible in order to spare them the care and expense of providing for their father, his fool, and a hundred knights. Lear not only deludes himself that he is going to live beyond the average life expectancy, but that his daughters are so much in love with him that they will enjoy playing hostesses for as long as he survives.
In Measure for Measure, Shakespeare expresses a more realistic attitude of children toward their aged parents when he has the Duke Vincentio, disguised as a friar, tell the imprisoned Claudio a number of reasons why he should look forward to being executed, including the following:
Friend hast thou none;
For thine own bowels, which do call thee sire,
The mere effusion of thy proper loins,
Do curse the gout, serpigo, and the rheum,
For ending thee no sooner.
Lear will soon learn this truth from Goneril and Regan, while in the subplot Gloucester will learn the same truth from his bastard son Edmund.