Estate planning attorneys always remind clients that if there are significant changes in their lives they need to revisit their estate plans and make any necessary changes.
Having more children definitely counts as a significant change in a person's life. Despite the advice of the attorneys, many people do not change their wills after they have more children.
That means courts have to decide what to do about the children and the will.
In Georgia the will gets revoked, as the Wills, Trusts & Estates Prof Blog discusses in "State Law on After-born Children Leads to Revocation of a Will."
In a recent court case, a Georgia man created a will in 1989. He later had three children out-of-wedlock, but he never updated his will to include the children.
The Georgia court decided that the will was, therefore, invalid and revoked it.
The man's estate would thus be distributed according to the state's laws of intestacy, as if the will never existed at all.
Every state treats these after-born children (who are not mentioned in wills) differently.
Talk to an estate planning attorney about the laws in your state.
Better yet, ask the estate planning attorney to help you update your estate plan, if you have had more children since you created your will.
Reference: Wills, Trusts & Estates Prof Blog (Oct. 17, 2017) "State Law on After-born Children Leads to Revocation of a Will."