I had a look at the 1880 census, out of curiosity.
There's one record I don't know if you saw. It's for Derby, New Haven, Connecticut, pg. 156C, ED 67. It contains a Fraher family. The mother, 43-year-old Mary, was born in Ireland and is apparently a widow. She has a daughter Mary who's 13. The daughter's father was born in Ireland, but her middle initial is given as "E". And she has 4 younger siblings but no sisters named Sarah or Elizabeth.
So this is probably not the Fraher family you're looking for, but there are enough similarities that I wanted to make sure you knew about it.
Oro Valley, AZ, USA