Ieuan was the son of Ieuan ap Rhys and Gwenllian verch Elidir. The date and place of his birth have not been found.
His wife was Tangwystl verch Llywelyn. They were married, but the date and place have not been found. Their three known children were Gruffudd Gryg ap Ieuan (?-?), Rhys Fongam ap Ieuan Fychan (?-?) and Dafydd ap Ieuan Fychan (?-?).
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Maredudd ap Owain |
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Elidir Ddu ap Elidir |
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