Four of Custer's relatives were killed.

The Battle of the Little Bighorn commonly referred to as Custer's Last Stand was a battle between combined forces of the Lakota, Northern Cheyenne, and Arapaho tribes and the 7th Cavalry Regiment of the United States Army. The battle, which occurred June 25–26, 1876, near the Little Bighorn River in eastern Montana Territory.

Nearly a whole generation of Custers fell at the Battle. The roster of the dead included Lt. Col. George A. Custer, 36, and his brothers Capt. Tom Custer, 31 (During the Civil War, Tom Custer won two Medals of Honor four days apart) and civilian guide Boston Custer, 27; their sister Margaret's husband, 1st Lt. James Calhoun, 31; and nephew Henry Armstrong Reed.

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