Following in the pawprints of Fala, Barney W. Bush became the second Scottish terrier to fetch, sit, and roll over in a wartime White House. Although his master proved to be nowhere near as popular as Fala’s, nip-prone Barney established a sizable fan base of his own during his stay at 1600 Pennsylvania Ave. thanks in part to his own page within the White House website and a series, 11 in total, of pooch propaganda films released during the Bush administration, including “Barney Reloaded” (2003), “Barney’s Holiday Extravaganza” (2006) and Barney Cam VI: Holiday in the National Parks.” Barney, who was later joined in the White House by his niece, Miss Beazley, comes from prestigious stock: His late mother, Coors, belonged to Christine Todd Whitman, former governor of New Jersey and Environmental Protection Agency director.