In 1899 she married MacNair and joined him in Liverpool where he was teaching at the School of Architecture and Applied Art. The couple painted watercolours and designed interiors, exhibiting a Writing Room at the International Exhibition of Modern Art in Turin, and Frances began teaching. They also designed the interiors of their own home at 54 Oxford Street. In the early 1900s they also exhibited in Liverpool, London, Paris, Venice, Vienna and Dresden. The closure of the School in 1905, and the loss of the MacNair family wealth through a business failure, led to a slow decline in their careers, and they returned to Glasgow in 1909. In the years that followed, Frances painted a series of symbolist watercolours addressing the choices facing women, such as marriage and motherhood. Frances and Herbert had a son, Sylvan, born in June 1900 and who later emigrated to Rhodesia.