Your heirs are the people who will receive your estate if you die without a Will. Your heirs are only identified after a person’s death. Until then, the people described in this post are potential heirs.
There are several categories of people who could be your heirs. The first category is your direct descendants. This means your children, grandchildren, etc. The second category is your parents, if living, or their descendants. In other words, your brothers and sisters, neices and nephews and so on. The final category is your grandparents, if living, and their descendants. So your aunts and uncles, cousins, and so on.
Your heirs are the living people at the nearest degree of kinship. And once a living heir is found, more remote categories are not counted. But within that degree of kinship, everyone is treated equally, whether living or dead.
For example, suppose you are an only child and die without descendants. Your parents have also died, but you have a living aunt on your father’s side and she has three children. Also, your mother’s brother has died but he had two children, your cousins. In that example, your aunt is an heir, as are the cousins on your mother’s side of the family. Your aunt’s children are not “heirs” because their mother is still living.