First off,
The question is an actual Earth (American version, if jurisdiction matters) legal one
It was inspired by Star Wars Episode VII, "The Force Awakens" related question on SciFi.SE site.
As such it contains spoilers for an important plot twist in the film, so please continue reading at your own risk.
Let's pretend that Millenium Falcon is a regular, Earth human trading freighter ship, registered to US flag.
It has an owner-captain (Han Solo), and a First Mate (Chewbacca) who is second in command. Both are US citizens.
Question: If the owner-operator dies - and absent any specific documents like a will, or joint ownership papers - does the First Mate inherit the freighter, in preference to the "standard" inheritance chain - wife and children? (assume that the wife is alive and can claim inheritance, to avoid complicated legal fallback scenarios)
If it matters, let's assume it's registered in whichever state LucasFilm (or Disney) headquarters are.