Why be baffled? Bride and Andreas are adjoining parishes. Not unusual to be born physically in one but attend church in the other.

1851 census Andreas district 5, entry 1, Kielushtay
William Sayle, head, married, 45, shoemaker, Andreas
Jane, wife, married, 37, Andreas
John R, son, unmarried, 16, Bride
Jane A, daughter, unmarried, 15, dressmaker, Bride
Elizabeth, daughter, unmarried, 13, scholar, Bride
William, son, unmarried, 9, scholar, Bride
Mary A, daughter, unmarried, 6, scholar, Bride
Thomas, L, son, unmarried, 4, Bride
Isabel, daughter, unmarried, 1, Bride