Conversation so far:
Where was O'Mara born?
CANNOTANSWER.
What was her family like?
flying instructor, and actress Hazel Bainbridge (born Edith Marion Bainbridge; 25 January 1910 - 7 January 1998).
Her younger sister is actress Belinda Carroll.
Did she have other siblings?
CANNOTANSWER.
Where did she go to school?
After boarding school she attended art school before becoming a full-time actress.

Question: What was her first acting role?
Self-contained rewrite: What was Kate O'Mara's first acting role?