Thanks, it looks like Jan 1880 is the right date.
Maryn, I'm not sure who his wife is. It thought it might be a Mary McCronk or McCrink because of the two children's births I found.
I can see I made a mistake - it was Margaret's death I found in 1880, not Mary's so she could still be alive in later censuses.
Is there a Mary Keating with children Adelaide b1877 and Catherine Anna b1879 in the next (1890?) census?