Lord Francis Douglas Marquess of Queensberry; a younger brother, Lord Archibald Edward Douglas (1850–1938), who became a clergyman; and a younger brother and sister, the twins Lord James Douglas (d. 1891) and Lady Florence Douglas (1855–1905), who married Sir Alexander Beaumont Churchill Dixie, 11th Baronet. He was an uncle of Oscar Wilde's lover Lord Alfred Douglas, and a younger brother of John Douglas, 9th Marquess of Queensberry. In 1858, Douglas's father, Lord Queensberry, died in what was reported as a shooting accident, but his death was widely believed to have been suicide. In 1862, his mother, Lady Queensberry, converted to Roman Catholicism and
Lord Alfred Douglas of Queensberry, suspected the liaison to be more than a friendship. He sent his son a letter, attacking him for leaving Oxford without a degree and failing to take up a proper career. He threatened to "disown [Alfred] and stop all money supplies". Alfred responded with a telegram stating: "What a funny little man you are". Queensberry's next letter threatened his son with a "thrashing" and accused him of being "crazy". He also threatened to "make a public scandal in a way you little dream of" if he continued his relationship with Wilde. Queensberry was well known for his temper