Margaret would be the last princess born to a reigning English monarch until the birth of  who's wife?
Margaret, Countess of Pembroke Margaret of England (20 July 1346 – October/December 1361) was a royal princess born in Windsor, the daughter of King Edward III of England and his consort, Philippa of Hainault. Margaret would be the last princess born to a reigning English monarch for over a century, until the birth of Elizabeth of York in 1466. She was also known as Margaret of Windsor.
Joan of Acre Joan of Acre (April 1272 – 23 April 1307) was an English princess, a daughter of King Edward I of England and Queen Eleanor of Castile. The name "Acre" derives from her birthplace in the Holy Land while her parents were on a crusade.