Frank,
There were, indeed, two Seborn Sneed Graham's. They are obviously related, but distantly at best. The one that served under Bryan and Adair in the IT was born 9-26-1835 in Taney Co., MO, son of Berry D. Graham and Sarah Wright. His family was residing in Benton Co., AR by 1850. He appl. for a Conf. pension in 1906 based on the above noted service. He died in 1908. The other Seborn Sneed Graham was born 1-24-1844 in Benton Co., AR, son of Ellis and Rebecca Graham. He married Susan Emily White 12-18-1873. He died 9-7-1898. His widow appl. for a Conf. pension from Benton Co. in 1914 based on his service in the 2nd Ark. Mounted Rifles.
Sources for the above are LDS records and Census records.
Hugh Keen