Thomas D'Umfreville
Thomas was born about 1360 in Harborrle Castle, Yorkshire, England.  He died about 1390.

 Agnes De Grey
Agnes was born about 1365 in Heton, England.  She died on October 25th, 1420.

 Margaret D'Umfreville
Margaret was born about 1390.  She died on June 23rd, 1444.