I don't think the 1880 census is the right family.
I wouldn't be so sure. The order of the children in the census are:
Mary
John
Margaret
Charles
Kate
Elizabeth
Jane
The obituary of the ALLEN child lists them as:
Mamie (ALLEN) - Mamie is pet name for Margaret or Mary
Clair (MORGAN)
John
Charlie
Kitty (pet name for Catherine)
Lillian (pet name for Eliza)
Jennie (pet name for Jane)
The main oddities look to be whether Mamie was actually Mary or Margaret and who was Clair .......... was she either Mary or Margaret?
I can see them I think in 1871 but Mary, the mother, has a birth place of Ireland there too

When did Mary Ann, the mother, die incidentally? Are all her children mentioned in her obituary and, if so, in what order and by what name?
Do you have other information on the family found in 1881 ie. finding them in later years which makes you think they are not the correct ones?
Casalguidi
