Mother and Three Children

Woman with three sweet young children; from a Curtis/Hope family collection. Logo is 'Robertson & Co., Muskogee, Ind. Ter'y'. Could have been taken in OK or northwest AR. Names might be Hope, Curtis, Martin, Boggs, Blake, or other.

Who is this family? Picture would have been taken before about 1900, since OK wasn't a state yet. How much earlier?