Question: In which battle did the Uncle of Henry Armstrong Reed and youngest brother of a US Army Lt Colonel and a two-time Medal of Honor Recipient get killed along with his brothers and his nephew? 
Facts:
Henry Armstrong Reed is the nephew of Boston Custer
Boston Custer is killed at the Battle of the Little Bighorn
Boston Custer is the youngest brother of U.S. Army Lt Colonel George Armstrong Custer
Answer: Battle of the Little Bighorn