Penelope Manley French (born c.1739) was the sister of Harrison Manley and the wife of Daniel French (c.1723–1771), a wealthy Fairfax County planter who lived at Rose Hill, about five miles west of Alexandria.  After the death of her husband, Penelope French remained at Rose Hill, along with her only child, Elizabeth (born c.1756).

Penelope owned lifetime rights in two parcels of land totaling over 500 acres, one on Dogue Run and the other south of Marshall’s tract. On her death the land would belong to Benjamin Tasker Dulany (c.1752–1816), husband to Elizabeth French. GW tried for a number of years to buy the land, but Mrs. French refused to sell. Finally, however, Dulany signed his and his wife’s rights over to GW in 1785. The following year Mrs. French relinquished her ownership to GW in exchange for land that GW had bought on Hunting Creek.

Penelope made occasional use of the blacksmith at Mount Vernon (see Ledger A, 298; Ledger B, 27).