Son of the Navy (1940)
Actually, the sailor wants nothing to do with the boy, who we eventually find out is an orphan who ran away from the orphanage, trying to find a new Mom and Dad. The sailor, not knowing anything about the boy, thinks he'll be more successful hitchhiking alone back to his ship. It's the boy who has the idea of pretending to be the sailor's kid, jumping into his arms, pretending to be a sick kid, prompting a well-meaning woman to pick them both up. The boy continues to pretend that the sailor is his dad, causing many problems for the sailor when everyone believes the boy, and doesn't believe the sailor. The movie continues, sometimes humorously, and often dramatically, as the main characters continue to grow closer together, becoming the family that they were not, before. An enjoyable diversion for a weekday afternoon (I'm watching it on FETV).