I'm not really clear on why you would encourage your son to confront an adult in such a combative way. You say you didn't see the letter before he called, but that seems like it should've been one of the stipulations of him doing this. You could've checked it for tone; the letter he read was presumptuous. I certainly wouldn't give money to a child who asked it of me in that way.

If you really felt like your son was being slighted, the better way would've been for you or your SO to handle it. I know that the goal of parenting is to get kids to learn to handle their own problems (though I don't necessarily agree there *was* a problem), but in this instance, an adult advocate could've kept this from escalating. Now he's sad because he didn't get paid and the SO's parents are pissed because they think your son is rude.

I agree with the other posters who say your SO should've been the one to pay your son if you feel like money should be exchanging hands. He's the one who invited your son along to work, not the SO's parents. They're not under any obligation to shell out money that wasn't agreed to.
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