In genealogy and wills, a person's issue are all their lineal descendants.
Lineal descendants
Issue typically means a person's lineal descendants—all genetic descendants of a person, regardless of degree.[1] Issue is a narrower category than heirs, which includes spouses, and collaterals (siblings, cousins, aunts, and uncles).[2] This meaning of issue arises most often in wills and trusts.[3] A person who has no living lineal descendants is said to have died without issue.
A child or children are first-generation descendants and are a subset of issue.[4]