According to my information taken from Chris Barber's book, 'More Mysterious Wales', Paladin, 1987, which he had obviously researched, "St Canna was the daughter of King Tewdr Mawr, and wife of Sadwrn (the brother of St Illtud) whose name is commemorated at Llansadwrn (Dyfed)" which is now Pembrokeshire. Crallo, a 6th Century saint, was the son of St Canna and St Sadwrn. There is also a church in Anglesey at Llansadwrn dedicated to St Canna's husband and on a tombstone there her name is inscribed.
There are two places called Llangan, one in Carmarthenshire (Pembrokeshire) and the other in South Glamorgan. St Canna's feast day is 25th October.
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