Who is Jack's Family from Four Plays and what is their importance?

Jack's family consists of Jacqueline, Mother Jack, Father Jack, Grandmother Jack and Grandfather Jack. They are each in their own way, an embodiment of the desire for control and convention. While they express themselves in absudist language, their intentions and determinations are essentially those of order..... the determination to impose control over chaos. Even the character of Grandfather Jack, who doesn't participate in the action, serves as a manifestation of order, or rather its after-effects. Grandfather embodies the paradoxical suggestion that in a crazy world, trying to attain control is itself an act of madness.