Check out the Ancestry Message Board - Royffe Royfee Family Tree Projecthttp://boards.ancestry.com.au/surnames.royffe/5/mb.ashx
I have recently attempted to draw together all the branches of the Royffe/Royfee family in an Ancestry Public Tree. I will send you an invitation to that tree, Royfee Royffe Public Family Tree.
The tree features your grandmother (1906 - 1990).
The Royffe family in England has a Heugenot background.
Your grandmother was a descendant of Peter Royffe (b. abt. 1784) one of the three sons of John Royffe (b. 1745) from whom the Royffe family in England and Royfee family in New Zealand are descended.