She married character actor
Al Ruscio in June 1954, and was known to her loved ones as "Jane Kate Ruscio". The couple had four children and remained together until Ruscio's death in November 2013. Less than one month later, Williamson died following a prolonged illness on December 6, 2013, aged 82, in
Encino, Los Angeles, California. She was survived by her four children and five grandchildren. ==References==