Yes, Mary had only 1 child, George Andrew Hopper, my father. He was actually a Justice for the 5th District Court of Appeal in California. He passed away in June, 1981 in Fresno, Ca. He was only 59years old. My mother is Grace L Duvall-Hopper.
My grandmother, Mary, passed away in 1984...I think. At the time she was in a convalescent home in Hanford, Ca. She had been living with my oldest brother's family in Hanford prior to this.
I think I'll start looking for this castle. I'll let you know if I find out anything