Question: James Calhoun was the brother-in-law of a soldier who was brevetted to brigadier general at what age?
Sentence (from "George Armstrong Custer"): Custer was brevetted to brigadier general at age 23, less than a week before the Battle of Gettysburg, where he personally led cavalry charges that prevented Confederate cavalry from attacking the Union rear in support of Pickett's Charge.
Relevant evidence: Yes