(25 October 1916 - 10 September 1920) (her death)
In late 1916, Thomas met actor Jack Pickford, brother of one of the most successful silent stars, Mary Pickford, at a beach cafe on the Santa Monica Pier. Both Thomas and Pickford were known for their partying. Screenwriter Frances Marion remarked, "I had seen her often at the Pickford home, for she was engaged to Mary's brother, Jack. Two innocent-looking children, they were the gayest, wildest brats who ever stirred the stardust on Broadway. Both were talented, but they were much more interested in playing the roulette of life than in concentrating on their careers." Thomas eloped with Pickford on October 25, 1916, in New Jersey. None of their family was present, with only actor Thomas Meighan as their witness. The couple would never have children of their own. In 1920, they adopted Thomas' six-year-old nephew when his mother died.