Walter's mother was a daughter of George Butler of Ballyragget, who belonged to another branch of the same wide-branched family.
[4][5] By his wife he had a son and three daughters:[6] He inherited his father's estate at an unknown time near the middle of the century and was then known as Walter Butler of Garryricken,[9] a member of the landed gentry.
In 1766, his cousin John Butler of Kilcash, the de jure 15th Earl of Ormonde, died without an heir.
Unknowingly, Walter Butler also inherited his cousin's title and became de jure the 16th Earl of Ormond.
They always owned large areas of land in counties Kilkenny and Tipperary, and now became the largest landowners in the southeast of Ireland.