The best anyone can give about that question is an approximation. Sybil was approximately 26 years old when she mentioned to her psychiatrist Cornelia Wilbur that her mother had died "a while back." Her father re-married around the time Sybil made this comment. Sybil's mother was over 40 when she had Sybil but no one is certain how much older. Based on Sybil's age and her vague referral to Martha's death she probably died in her mid to late 60's.
Casey Hageman died on 1964-04-01.
Johanna Hageman died on 1984-02-10.
Marshall Hageman died on October 26, 1940, in Los Angeles, California, USA.
Richard Hageman died on March 6, 1966, in Beverly Hills, Los Angeles, California, USA.
Casey Hageman died April 1, 1964, in New Bedford, PA, USA.
Marshall Hageman's birth name is Marshall John Hageman.
Alice Treff's birth name is Alice Martha Treff.
Martha Alice Aly has written: 'Ethical concepts for recreation professionals' -- subject(s): Recreation leadership
Casey Hageman was born on 1887-05-12.
Johanna Hageman was born on 1918-12-17.
Andrew Hageman was born on 1986-07-17.
Fred Hageman was born on 1937-06-30.