Hi Nickoli

I missed a comma after Hannah.....it should have read two other children to Joseph Grindy and Hannah,
Emily b. 1863 and James Bernard b. 1865 sorry to confuse you further.
If you are certain that Mary Ann McMahon's mother Hannah married Joseph Grindy did you get the marriage cert???
I am presuming that Mary Ann's birth cert had a blank for father.
Did Mary Ann get married and did that shed any clues to her father?
The other thing that you might get lucky with is Mary Ann's chr record. In some cases even when the child is illigit the priest/vicar will state the reputed father.
(but not in all cases).
There is such a thing as bastardy bonds too which if Hannah tried to claim money off the father then there could be records. I am not too well up on how to check these bonds but i'm sure some kind soul on here could point you in the right direction.
Did you ever manage to find Mary Ann on any of the census?? Will gladly take a look if you havent the info.
Anyway All the best with your research and the best of luck to you.
Angela.