The U.S. Congress passed an Act in 1862 granting pensions to the widows, children, and mothers of Union soldiers killed in the war. Widows were required to prove that they had been legally married and had not since remarried. Children qualified for pensions until they reached the age of 16. Mothers of soldiers were required to prove that they had been financially dependent upon their deceased sons.
Copies of Civil War pension records from the National Archives can be searched online at Fold3.com.