Intestate means dying without a valid will. It is not a legal limbo - Arizona has a complete set of default rules that decide who inherits, in what shares, in a fixed order: spouse, descendants, parents, siblings, and outward through the family tree.
The defaults are reasonable for the average family and wrong for many real ones. The sharpest edge is the blended-family rule: a surviving spouse with stepchildren in the picture can receive half of the separate property and none of the deceased's share of the community property. The statute does not know your family; it only knows categories.
Intestacy also decides who administers the estate and who raises minor children - all choices a one-page will would have kept yours.
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Educational information only, not legal advice. Terms have statutory details beyond these summaries - confirm your situation with a licensed professional.