How does Billy reunite with Boyd and how do they escape?

Billy asks where Boyd is and the sheriff says that Boyd, as a minor, cannot be released, especially considering Billy is also a minor. No one is home when Billy arrives at the house where Boyd is staying. Boyd arrives in a few minutes and says he's been waiting for Billy. The two steal some cash money, food, and supplies, including a shotgun. They ride away on Billy's horse, accompanied by the dog.