The Thomas Law House (Honeymoon House) was constructed between 1794 and 1796 in Washington, D.C. In March 1796, Thomas Law moved into the house after his marriage to Martha Washington's eldest granddaughter, Eliza Parke Custis. The house became known as "Honeymoon House" as the Laws lived there during their honeymoon while awaiting completion of their house. In 1816, former Congressman Richard Bland Lee and his wife Elizabeth (Collins) Lee purchased the house. During the Civil War, it was the Mt. Vernon Hotel. Starting around 1913, it was the Washington Sanitarium's Mission Hospital.