Una, the Thomas Cannell your grandmother visited in 1889 at Barragarrow was almost certainly the 66 yr old unmarried retired farmer Thomas Cannell who was living there in 1891. Following this TC back through the censuses, he’s with his parents, John and Isabella and a sister Elizabeth Cannell who looks as though she was his twin.

1841, JC 45, IC 45, TC 15, EC 15

1851
Ballacarnane Beg, Michael

Ancestry’s transcription:
Name Age
John Cannell 60
Isabella Cannell 60
Thomas Cannell 25
Elizabeth Cannell 25
Thomas Caine 17

notes:
JC freehold farming 33 acres b Michael
others b German

IGI has baptisms on the same day (19th July 1825) for Thomas and Elizabeth to John Cannell and Isabella Cowley.

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Trying to link your g g grandmother Ann Curphey nee Cannell to this particular Cannell family, the only clue I can find is that Ann must have been born between 1809 and 1813 because at her Malew marriage to William Curphey in 1829 she had the consent of her parents. But I can’t find an Ann Cannell baptism in Michael in this time frame. Perhaps she was born in Michael and baptised in a different parish, or she was illegitimate and baptised under a different surname.

If there is a link to the Ballacarnane family, it may be hard to prove. Perhaps Ann could have been an illegitimate daughter of John Cannell b 1791, born prior to his marriage (as a bachelor) to Isabella Cowley in 1821.

Jean C