I don't have anything yet on this Caine line.

However, Charles Caine in the 1881 census is Charles Caine Cox of the Peel Lifeboat. His parents were James Caine and Catherine Morrison.
I'm not aware of them having a John b abt 1842 ish

I think Ancestry is confusing sometimes with censuses. This is my copy of the 1881 Peel Census you mention above

1881 Peel
, 1, 4, 233, CAIN, Charles, 3 Circular Rd, Head, Married, 33, Master Mariner, Peel
, 1, 4, 233, CAIN, Elizabeth, 3 Circular Rd, Wife, Married, 28, Dressmaker, Michael
, 1, 4, 233, CAIN, Elizabeth, 3 Circular Rd, Daughter, , 7, , Michael
, 1, 4, 233, CAIN, James, 3 Circular Rd, Son, , 4, , Michael
, 1, 4, 233, CAIN, Charles, 3 Circular Rd, Son, , 3/12, , Peel
, , , .
, 1, 4, 234, COOLE, Henry, 3 Circular Rd, Head, , 27, Fisherman, Peel
, 1, 4, 234, COOLE, Esther E., 3 Circular Rd, Wife, , 32, , Braddan
, 1, 4, 234, COOLE, William H., 3 Circular Rd, Son, , 1, , Peel
, 1, 4, 234, CAIN, Margaret, 3 Circular Rd, Daughter, , 10, Scholar, Peel
, 1, 4, 234, CAIN, Annette, 3 Circular Rd, Daughter, , 8, , Peel
, 1, 4, 234, CAIN, Elizabeth, 3 Circular Rd, Daughter, , 6, , Peel

Donna
, , , .