Seems to be an elusive family.
1910 census Galveston Co, TX:
Whitson, Frank, h, 54, wid, b TN, TN, TN
[Index shows middle initial "F", but handwritten record looks more like an "S" to me.]
1930 census Denton Co, TX:
Whitson, Warren P., h, 40, M @25 yrs of age, b CO, TN, IA
" Oda Joe(sic), w, 36, M@ 21 yrs of age, b TX, LA, KY
" Warren Jr., s, 11, b TX
" Billy, s, 10, b TX
" John M., s, 7, b TX
1920 census Denton Co, TX:
Whitson, W.P. Mr., h, 31, md b CO, IA, U.S.
" Odie Jo(sic), w, 27, b TX, LA, KY
" W.P. Jr., s, 1 2/12, b TX
Now, on the 1900 census this looks like the above Warren living with his parents and family, and Warren (sr) is probably the son Warren Pickard Whitson, but last name is spelled unusual, and handwriting really not clear.Also, place of birth of father and son are certainly "off." But, it wouldn't be the first error I've seen on census records.It will give you something on which you can follow up on and see if you can find anything more on this family.
1900 census Navarro Co, TX:
Whiston, Warren, h, b J__, 18??, 32, M 10 yrs, b MS, MS, MS
" Mamie, w, b Jan 1873, 23, M 10 yrs, 4 ch, 4 lvg, b FL, FL, FL
" Warren, s, b May 1891, 9, b TX
" Erma, d, b Jun 1893, 6, b TX
" Elver, s, b Mar 1895, 5, b TX
" Hubert, s, b Feb 1900, 2/12, b TX
[Index shows surname as Whiten, but there is another letter in the name and I think it looks like Whiston.]
If the Warren who was born 1891, was born in CO, the family should be there, but I don't see them there on the 1880 census, in fact I don't see Frank Sr, or Frank Jr, anywhere on the 1880, nor any Geneieve, either.
Have you obtained a copy of Geneieve's death certificate?It should show the names of her parents, if the informant had the knowledge.
Do you know where the Whitsons or Packards were from prior to CO?