What plot is happening in chapter 17

Chapter 17 depicts Joey's transfer from the front lines to a veterinary hospital. He is weary, hungry, covered with mud, and (due to his injured leg) in some pain. A gruff officer notices Joey's condition and sends Joey off with a young man, who will make sure that the new arrival is cleaned and cared for. Though still somewhat disoriented, Joey listens to what this young man is saying and learns that his caretaker, in fact, is Albert. The young man reveals—in the course of a conversation with another enlisted man, David—that he had joined the veterinary corps in order to find Joey. David had remained skeptical that Albert would succeed, but as Joey is cleaned, the two men realize that they may be in luck. As the mud disappears, Joey's distinctive white markings are revealed. Albert, astonished, uses one further measure—a distinctive owl whistle call—to test and confirm Joey's identity. Finally, Joey and his master have been reunited.