What a pity,
it seemed a good match for place too.
Other comments:
My great-grandparents's aunt (who had lived with the family for many years) got confused on one census about which of their two eldest children was born in England (the rest all in Dublin). I have the original as well as a copy cert showing that it was my grandfather but in 1901 his older brother was listed as England and himself as Ireland.
I have come across families in my tree where even the parents seem to have got confused between birthdays of their children on the US census (many children, right birthday, wrong child or vv!)
Perhaps, if the child wa not strong, she actually travelled out with a relative, a little later than the parents, after they had time to settle. Have you checked for her on other voyages?