I know censuses can have errors, but the birth year you have may be wrong for Susan.
1900 census Ohio Co, KY:
Cummins, Robert H., hd, b June 1863, 36, Md 6 yrs, b KY, KY, KY
" Susan J., w, b Sep 1875, 24, Md 6 yrs, 2 ch, 2 lvg, b KY, TN, KY
" John M., s, b (Nov ?) 1894, 5, b TX
" Cliffie, d, b Apr 1898, 2, b KY
1910 census Ellis Co, TX:
Cummins, Robert H., hd, 46, M (1) 17 yrs, b KY, KY, KY
" Susan, w, 34, M(1) 17 yrs, b KY, TN, KY
" Willie, s, 15, b TX
" Cliffy, d, 12, b TX
" Eva, d, 8, b TX
Note, previous census showed Cliffie/Cliffy b in KY
Next door, I would think there is a relationship here, maybe Josie's first husband was a brother of Robert(?):
Freeman, Sam A., hd, 40, M(2) 11 yrs, b TN, TN, TN
" Josie, w, 35, M(2) 11 yrs, b KY, KY, KY
" Jewel, d, 10, b TX, TN, KY
" Eugene, s, 8, b TX, TN, KY
" Earl, s, 5, b TX, TN, KY
Cummins, Kate, stepdaughter, 14, b TX, KY, KY
Three pages away, is this your Susan's brother?
House, John L., hd, 37 M(1) 15 yrs, b KY, KY, KY
" Rosa M., w, 32, M(1) 15 yrs, 2 ch, 2 lvg, b KY, KY, KY
" Ina L., d, 14, b TX
" Minnie M., d, 10, b TX
Doing a search on the 1880 census for a Gabie Brown, the only one that shows up anywhere in KY is the following, and the House siblings are not listed there.Could not find a Morrison or Luke Brown on 1880 census.
1880 census Rockport, Ohio Co, KY:
Category: Name;Relationship to head of household; Marital Status; Gender; Race; Age; Birthplace; Occupation; Father's Birthplace; Mother's Birthplace.
Gabie A. BROWNWifeMFemaleW24KYKeeping HouseVADE
W. T. BROWNBrotherMaleW30KYLaborerVAKY
Doing a search for Susan House, I found the following family, and they also have a son named John -- certainly not proof it is your family, though.
1880 census Sharpsburg, Bath Co, KY:
George HOUSESelfMMaleW37KYFarm LaborerKYKY
Hanah J. HOUSEWifeMFemaleW39KYHouse KeeperKYKY
Carline HOUSEDauSFemaleW16KYHouse WorkKYKY
Nancie A. HOUSEDauSFemaleW14KYNot EmployedKYKY
Sarah B. HOUSEDauSFemaleW12KYNot EmployedKYKY
John T. HOUSESonSMaleW10KYNot EmployedKYKY
Susan HOUSEDauSFemaleW8KYNot EmployedKYKY
Leana HOUSEDauSFemaleW6KYNot EmployedKYKY
William W. HOUSESonSMaleW4KYNot EmployedKYKY
Susan said she was born in Rochester, do you suppose it actually was Rockport, where Gabie and Lewis resided?I would check probate and guardianship records in Ohio Co, see if you can find anything on a House that could be the father of Susan and John.Also, check out Butler Co, where Susan said she was born.
Happy Hunting (^_^)