John De Cogan
John was born about 1169 in Bampton, Devonshire, England.  He died in Cogan, Glamorganshire, Wales.

 Marie De Prendergast
Marie was born about 1172 in Douglas, County Cork, Ireland.

 Juliane De Cogan
Juliane was born in 1195 in Salisbury, Wiltshire, England.  She died at the age of 62 in 1257.