Nice to hear of more interest here..
I have provenance from pictures of Indian chiefs collected by H.W. Andrews (BIA administrator from that era) that notes James C Robb was born in Ohio in1845, moved with his wife, two year old son, cousin, two servants and ranch hand to Ft. Bennett "by" 1880.
Cabinet card of Little Raven an Arapahoe Chief. P 326
I grew up on Robbs Flat, and am looking for origins of the name.