I belong to Ancestry and did my searching there (see above). Any of us who predecease your sister should greet her when she passes assuming the famous Seth portrait look and pose.
From the coming of Seth (early titled how to develop your esp power )published by pocketbooks Session 1 Frank Withers was spelled on the ouijaboard dead of death 1942
Frank Withers is the name Jane used to protect any individual’s privacy. She did reside in the same area and did not want to offend anyone.
It is later disclosed in the Seth Material that the real name is Frank Watts.
I am not a Worldwide member of Ancestry anymore, but a search of the site brings up a 1915 census record for Elmira with the name Frank Watts. Any American members (I am in UK), might be able to get the actual image with more info on.
New York, State Census, 1915▼
Census & Voter Lists
Name: Frank C Watts
Spouse: Kathrine L Watts
Birth: abt 1882 - United States
Residence: Elmira Ward 12, Chemung
From TES BOOk 1 page 224:
Frank exaggerated to some degree about his relationship with Miss C.
They met often over a period of years because she taught his kids and he admired her and his children thought she was an excellent teacher.
Frank considered her a friend and he attached more importance than she did to get influence upon his children.
Miss C doesn’t remember also because she was in the process of disentangling herself from this plane and didn’t remember.
Of the name Frank Watts and aka Withers, I recalled hearing from someone in-the-know, neither were his real name.
I reached out to check with Mary Dillman. She’s the best keeper of Seth work details I know.
She confirms with certainty:
The only names Jane and Rob used were Watts and Withers.
My guess is whoever was in-the-know was mistaken.