The electoral register lists Joan living with her husband John Ernest Collins at 22 Hilary Avenue, Mitcham from 1964 on. She was no longer listed with him in the 1972 register and so depending when the register was taken probably died between 1970 and 1972 when she was in her mid-30s. I have not found a record of her death in those or any other years, or in newspaper reports. Relatives believe that she may have drowned, possibly in the River Thames. John continued to live at 22 Hilary Avenue until his death in 1989 age 58.