Slight coincidence - I have been researching the Abbett family, whose children were born in the 1805 to 1840 range. Some of them moved to Johnson County, Indiana, others to Bartholomew County, Indiana. The Indiana State Library has a list of Civil war volunteers from Indiana. That might help you. If you can identify his unit and if he is a Union soldier, the National Archives can supply his military record and with a seperate application will also send his pension file (even if his widow applied).