When was the British financial analyst to whom Sophie Winkleman was a wife born? 
Sophie Winkleman:  As the wife of Lord Frederick Windsor, son of Queen Elizabeth II's first cousin Prince Michael of Kent, she is formally referred to as Lady Frederick Windsor, but continues to use her maiden name in her professional career. Lord Frederick Windsor: Lord Frederick Windsor (Frederick Michael George David Louis; born 6 April 1979), also nicknamed Freddie Windsor, is a British financial analyst, and the only son of Prince and Princess Michael of Kent.
6 April 1979