You may be looking for her niece, Marguerite Rutherford, née Blakeney.
Marguerite Blakeney was one of the children of Sir Percy Blakeney and Alice Clarke Raffles. She married Paul H. Delagardie, the orphaned son of one of the French aristocrats whom Sir Percy had saved from the Revolution.
Paul and Marguerite were the parents of Francis Delagardie, all four of whose grandparents had witnessed the Wold Newton Meteorite and been bathed in its beneficial ionizing radiation. It is therefore not surprising that his grandchildren Lord Peter Wimsey and Richard Wentworth were both outstanding men in their various fields.