Ingrid,

This is the information available for your Andrew V. P. Day. According to his pension application, he served in both the 10th Ohio Cavalry and the 86th Ohio Infantry. He applied for and received an Invalid Pension in 1879 and his widow received a pension in 1911. If you don't have these documents, they are available through the link below.

Jim Martin

Name: Andrew Day ,
Enlistment Date: 3 Oct 1862
Service Record:
Enlisted as a 2nd Lieutenant on 3 October 1862 at the age of 25.
Promoted to Full Captain on 15 Jan 1863.
Commission in Company F, 10th Cavalry Regiment Ohio on 3 Mar 1863.
Resigned Company F, 10th Cavalry Regiment Ohio on 17 Dec 1863.

Name: Andrew Day ,
Enlistment Date: 27 May 1862
Service Record:
Enlisted as a Captain on 27 May 1862 at the age of 25.
Commission in Company I, 86th Infantry Regiment Ohio on 10 Jun 1862.
Mustered Out Company I, 86th Infantry Regiment Ohio on 25 Sep 1862 at Camp Chase, OH.