Katherine (or Katharine or Catherine) (c. 1350 - May 10 1403), was the daughter of Payne (or Paen) de Roet (or Rouet or Roelt) a Flemish herald from Hainault who was knighted just before his battlefield death. His children included Katherine, her older sister Philippa, a son, Walter, and the eldest sister, Isabel (Elizabeth) de Roet, (who died Canoness of the convent of St. Waudru's, Mons, c. 1366). Wikipedia
The definitive Wikipedia entry for Katherine Swynford. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Katherine_Swynford
The aims of the Society are (1) to celebrate the life and times of Katherine Swynford, who died in 1403, and (2) to raise money for Kettlethorpe Church and Lincoln Cathedral www.katherineswynfordsociety.org.uk