In Pulp Fiction (1994), Captain Koons says to Kid:
Captain Koons: See, I was a good friend of your dad's. We were in that Hanoi pit of hell together...over five years. Hopefully...you'll never have to experience this yourself, but when two men are in a situation like me and your dad were...for as long as we were, you take on certain responsibilities of the other. If it'd been me who'd--not made it, Major Coolidge'd be talking right now to my son Jim. But the way it turned out, I'm talking to you.
What does "of the other" mean?