Buchanan’s niece Harriet Lane—the daughter of Buchanan’s sister Jane—served as the White House hostess during President Buchanan’s tenure in office. Harriet’s mother and father had died by the time she was eleven years old. James Buchanan became her guardian and took care of her.

Buchanan also took care of his nephew James Buchanan Henry, the son of Harriet Buchanan and James Henry. When his parents died, James Buchanan also became young James’s guardian. Buchanan educated his nephew, including paying his way to Princeton University. James Buchanan Henry served as secretary to the president for his uncle and later became an assistant U.S. attorney in New York