The above also applies to PC vs. PC interaction. Social skill mechanics should never be used between PCs. One PC should never be allowed to roll a persuasion check to convince the other PC to do something. This is the same as telling the player how their character feels, except that it’s even worse, because it’s not the DM, it’s another player doing it. If one PC wants to convince another PC of something, they have to roleplay it out, or at least talk to the other player and try to convince them the old fashioned way. Same goes for lying or hiding things from another player. You can’t just have a PC roll and say it works. The tricked player will hate it, because the player knows what’s going on, and you’re taking away their ability to decide how their character would react.