There is this baptism from FamilySearch.org which could be her, but Kelly is a very common name:

Isabella Kelly
Isle of Man Births and Baptisms, 1607-1910
Name: Isabella Kelly
Gender: Female
Christening Date: 11 Jan 1829
Christening Place: BRADDAN,ISLE OF MAN
Father's Name: Wm Kelly
Mother's Name: Isabella Clague

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