Owain Cyfeiliog ("Cyfeiliog") ap Gruffudd
Owain Cyfeiliog, known as "Cyfeiliog", was born about 1125 in Montgomeryshire, Wales.  He died in 1197 in Strata Marcella.  He was buried in Strata Marcella.

 Gwenllian verch Owain I
Gwenllian was born about 1124 in Caernarvonshire, Wales.

 Gwerful verch Owain Cyfeiliog
Gwerful was born about 1144.

 Gwenwynwn ap Owain
Gwenwynwn was born about 1151 in Montgomeryshire, Wales.  He died in 1216.