Nielsen Hayden genealogy
Family: Henry de Percy / Mary of Lancaster (F11215)
m. Bef 5 Sep 1334-
Father | Male
Henry de Percy
Born Between 1322 and 1325 of Alnwick, Northumberland, England 
Died Abt 18 May 1368 Warkworth, Northumberland, England Buried Alnwick Abbey, Northumberland, England Married Bef 5 Sep 1334 [1] Father Henry de Percy | F3344 Group Sheet Mother Idoine de Clifford | F3344 Group Sheet
Mother | Female
Mary of Lancaster
Born Abt 1320 Died 1 Sep 1362 Buried Alnwick Abbey, Northumberland, England Father Henry of Lancaster | F1680 Group Sheet Mother Maud de Chaworth | F1680 Group Sheet
Child 1 | Male
+ Henry Percy
Born 10 Nov 1341 of Warkworth, Northumberland, England Died 19 Feb 1408 Bramham Moor, near Tadcaster, Yorkshire, England Buried York Cathedral, York, Yorkshire, England Spouse Margaret de Neville | F11212 Married 12 Jul 1358 Brancepeth, Durham, England
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