Piers FitzThomas Butler

Piers FitzThomas Butler of Duiske (died 1601), was the illegitimate son of Thomas Butler, 10th Earl of Ormond. The lands of Duiske Abbey had reverted to his father. In 1597, the earl executed a deed of conveyance in his favour for the lands (when Piers had reached maturity).
Marriage and issue.
He married Katherine Fleming, the eldest daughter and co-heiress of Thomas Fleming, 10th Baron Slane and Catherine Preston. They had two sons. Piers was succeeded by his eldest son. Sir Edward Butler of Duiske, knt. On 16 May 1646, Edward was created Viscount Galmoye.