Building on what Sheri found, the family is in Lincoln Co, AR in 1880. Maybe first marriage for Charley might be found in that county???:
Here is Sylvanus apparently with a new, younger wife, page 93B:
Category: Name;Relationship to head of household; Marital Status; Gender; Race; Age; Birthplace;; Occupation Father's Birthplace; Mother's Birthplace.
Sylvanus RAINSSelfMMaleW48SCLaborer------ Mary RAINSWifeMFemaleW26ARKeeps HouseNYTN Callie RAINSDauSFemaleW1ARSCAR Christopher RAINSSonSMaleW1MARSCAR Fanny GRIFFINOtherWFemaleB18ARLaborer------ George GRIFFINOtherSMaleB7MARARAR
Maybe the grown Rains children didn't get along with new "mother." Here's Maggy married, and living with her and her husband two of her siblings. They include Charley, page 95B
And Mary with husband and two children along with brother Eliga, page 95A:
Roselvo SAINTSelfMMaleW26MSFarmerTNIL Mary SAINTWifeMFemaleW24SCHouse KeepingSCSC Harvy W. SAINTSonSMaleW1ARMSSC Albert R. SAINTSonSMaleW2MARMSSC Eliga RAINSBrotherSMaleW19SCSCSC
You know, if the Charles Raines on Chickasaw Co, IT, 1900 census is your man, just a couple of pages away is an Eliga, about the right age to be the brother of the Charles in Lincoln Co, AR census records. Birth location for him and his parents do not match, but then again, neither do the ones for Charles on this census. Common mistake for census records. I think Sheri found your man.
Go to the Lincoln Co, AR GenWeb site -- http://www.argenweb.net/lincoln/http://www.argenweb.net/lincoln/ -- Click on Marriage Records. They have a volunteer listed who will do marriage look ups 1879 to 1895. See if Charles or Eliga show up.