Sir Thomas Willoughby
Sir Thomas was born in 1380 in Eresby Manor, Lincolnshire, England.  Sir Thomas is no longer alive.

 Elizabeth De Neville
Elizabeth was born in 1384 in Raby, Durham, England.

 John Willoughby
John was born in 1402 in Guisborough, Lincolnshire, England.  He died in Kirton, Lincolnshire, England.

 Margaret Willoughby
Margaret was born in 1410 in Guisborough, Lincolnshire, England.  She died at the age of 42 on October 22nd, 1452 in Ormsby, Lincolnshire, England.