Shortly after his father’s death in 1718, Walter Cooper (1696-1751) extended the house to the west, thus completing the main block of the house and presenting a symmetrical façade. The earliest remaining window sash in the house dates from Walter Cooper’s ownership. Walter Cooper married Martha Goddard on January 1, 1722. His will, dated September 18, 1751, directed that his wife Martha “should have the West half of the Dwelling house and the liberty of ovens on t’other room” and that his son Walter Cooper Jr. have the “East half of my dwelling house and the New shingles to repair it” together with the western half at the widow’s death. Individual family members occupied two different sides of the house, a common arrangement at the time.
The house descended through the Cooper family until 1788 by a complicated set of property conveyances until it was deeded to Gideon Frost, a grandson of Samuel Cooper, the original builder. Gideon’s parents were Edmund Frost and Samuel’s daughter Hannah Cooper.