This looks like a good possibility to be Robena?

From the IGI, extracted record (from the parish register):
RUBENCE ELEANOR KNEALE Christening: 24 APR 1870 Ballaugh, Isle Of Man, Father: JOHN KNEALE, Mother: ELIZABETH BARRON.

Also (extracted entry):
WILLIAM KNEALE Christening: 22 APR 1866 Sulby, Isle Of Man, Father: JOHN KNEALE, Mother: ELIZABETH BARRON.

Possibility to be Mona aged 9 in 1881 (extracted entry):
ELIZA MONA KNEALE Christening: 01 MAY 1872 Kirk Michael, Isle Of Man, Father: JOHN JAMES KNEALE, Mother: ELIZABETH (no surname).

There were a few others with Elizabeth mother, no surname, but not Sarah as yet.

JOHN KNEALE & ELIZABETH BARRON married 22 OCT 1859 Kirk Michael (IGI extracted record).

If you look at the above marriage and bapt entries on film in the MNHL you may pick up other useful details about the family.

Sue