Petey the pig contains multitudes. He is a beloved member of the Forgione household in suburban Whitestone, Queens. He is a bona fide form of prescription medicine. He is an enemy of the New York City department of health. And on a spring afternoon walk with his owner, Danielle Forgione, 1-year-old Petey is just a pig pursuing wholesome piggish endeavors: snorting, grazing, rooting through the dirt, searching out bugs.
Petey is certified as an emotional-support animal (ESA), and Forgione could use the support. Her father has brain cancer, her brother was killed in a motorcycle accident in March 2012, and she...