BA disappeared during a thunderstorm in Raleigh. Seven years later, a shelter in Durham scanned his microchip and found the owner listed in the records. Kessler had moved to Arizona by then. BA was flown across the country to meet him again. And when Kessler gave him some of the commands he'd known years earlier, BA still remembered them.
There's another story like this one waiting — of something lost, and someone who never stopped hoping.