William I de Ros
William I was born in Helmsley, Yorkshire, England.

 Lucia FitzPiers of Brecknock
Lucia FitzPiers of was born about 1196 in Helmsley, Yorkshire, England.  She died after 1266.

 Robert IV de Ros
Robert IV was born before 1237 in Hamlake Castle, Yorkshire, England.  He died on May 17th, 1285.

 William II de Ros
William II was born about 1244 in Ingmanthorpe, Yorkshire, England.  He died before May 28th, 1310 in England.  He was buried before May 28th, 1310 in Gray/Grey Friars, Yorkshire, England.

 Alice de Ros