However, the share is not automatically paid. The surviving spouse must "elect" to take the share. The spouse has 6 months from the date of death or the date of probate, whichever is later, to make this election. It is made by filing a claim with the Clerk of the Orphan's Court in the county of the decedent's domicile.
It should be noted that, if the surviving spouses makes the election to take the 1/3 share, then he or she gives up any other provisions that were made for him or her. Making the election is considered to be a disclaimer of all benefits passing to the surviving spouse under the Will. Additionally, certain interests are not subject to the election. For example, any transfers made with the consent of the surviving spouse; life insurance on the decedent's life, or retirement plans. Finally, if there is a pre-nuptial agreement or post-nuptial agreement, the surviving spouse may have waived their right to make this election.
Since I don't have all of the facts of the case, your father's wife needs to consult with an estate/probate attorney as to all of this.