Daisy Fellowes (née Marguerite Séverine Philippine Decazes de Glücksberg; 29 April 1890 – 13 December 1962)[1] was a prominent French socialite, acclaimed beauty, minor novelist and poet, Paris editor of American Harper's Bazaar, fashion icon, and an heiress to the Singer sewing machine fortune.

After her mother's suicide, she and her siblings were largely raised by their maternal aunt, Winnaretta Singer (Princess Edmond de Polignac), a noted patron of the arts, particularly music.

He reportedly died of influenza on 20 February 1918 while serving with the French Army in Mascara, Algeria, though there was gossip that he actually committed suicide as a result of his homosexuality having been exposed.

Their country estate was Compton Beauchamp House in Oxfordshire, where they raised three daughters: Of her Broglie children, the notoriously caustic Fellowes once said, "The eldest, Emmeline, is like my first husband only a great deal more masculine; the second, Isabelle, is like me without guts; [and] the third, Jacqueline, was the result of a horrible man called Lischmann ...."[5] Her second husband, whom she married on 9 August 1919 in London, was The Hon.

She married her second husband in 1953 (divorced), Tadeusz Maria Wiszniewski (1917–2005); they had one daughter, Diana Marguerite Mary Wiszniewska (born 1953).