Arthur’s third son by his first wife, William Livingston Erwin was born in Ireland in 1760. He arrived in Philadelphia in August of 1768 when he was eight years old. William grew up in Upper Bucks County. During the Revolutionary War, he was commissioned as a captain of the First Company, Third Battalion of the Bucks County Militia on May 14, 1781, at the age of 21, and as Captain of the 8th Company of the Bucks County Militia in 1786. He also served as Wagon Master of a brigade of wagons in 1778/79. He was made Colonel in the Fourth Regiment on Aug. 1, 1793.
Together William and Achsah had five children: Mary, Rachel, Scott, Juliana, and Charlotte. They lived with William’s Father at the Red House Farmstead. When Arthur died, Joseph (the second-born son) inherited the family homestead. However, as Joseph lived in Philadelphia, William continued living at the Red House Farmstead. Upon his death in 1807, Joseph willed this property to William.
William served as a member of the Pennsylvania State Senate from 1808 to 1816. During this time, William served as a “Gentleman Farmer.” In 1798, William purchased an additional 126 acres of land in this area, including the land on which the Erwin Stover house still stands. He built the original south section of the house between 1798 and 1820 in the Federal Style, but rather than farm the land himself he leased the house to tenants who were charged with managing the 126-acre farm.
William died in 1836 leaving the property to his daughter who continued to lease it as a tenant farm. In 1845, William’s daughter died and the Erwin property was listed for sale in the Bucks County Intelligencer. It was described the property at this time as “a good two-story brick mansion house with two rooms and a large hall below and three rooms above with a kitchen adjoining, and a cellar underneath; a wash house and well of excellent water near the door; a large, frame barn, convenient wagon house and corncribs adjoining.”