Harriett Sarah Moncreiff was born in 1848 to Sir Thomas Moncreiffe, a Scottish baronet, and Lady Louisa Hay-Drummond, per My Heritage. While still a teenager, she became part of the inner circle of the Prince of Wales and his wife Princess Alexandra, a Danish royal, whom Prince Edward married in 1863, per the Daily Mail. When Harriet married Sir Charles Mordaunt in 1866, Edward gave her a jewel-encrusted ring as a wedding gift and later gave her two ponies. When Charles came home early from a hunting trip to find the prince at his house, he shot the ponies in front of his wife. There was plenty of evidence the prince and Harriet had a long-running affair.
Following the birth of Harriet's child in 1869, who was born temporarily blind, which she believed was due to venereal disease, she confessed to her husband, per the Vancouver Sun. "I have been very wicked with the Prince of Wales, Lord Cole, Sir Frederick Johnstone, and others, and in open day," she told him (via "An Official Report of the Cause Célèbre Mordaunt V. Mordaunt, Cole, and Johnstone"). Charles filed for divorce even though he'd been pressured by the royal family to keep it quiet. Sir Thomas Moncreiffe, Harriet's father, pushed to declare his daughter insane in order to prevent the case from moving forward. The court found Harriet insane and she spent the rest of her life, 33 years, locked away.
