Keep the Children Out of It
When parents argue, leave the kids out of the fight. That doesn't mean you should bury your disagreements or pretend everything is fine. Settle what you need to settle. But the moment a child gets pulled into the conflict and told to choose a side, something goes wrong that's hard to undo. Divorce makes this risk sharper, because suddenly the child isn't a bystander anymore.
There's a name for it: triangulating. Two people have a problem with each other, and instead of working it out between themselves, one of them drags in a third person and pressures that person to pick a side. Most arguments have two versions of the truth. If you've only heard one of them, what business do you have taking a side at all? And even if you knew both sides, would you want to? Is the fight worth losing someone over?
You see this all the time when a marriage falls apart, and it's at its ugliest when a child is the third point of the triangle. It often means lying to the child about what really broke down, and about who, if anyone, caused it. The parents may walk away as strangers to each other once the papers are signed. The child can't. He still has a mother and a father, and he's the one left carrying both sides of a quarrel that was never his.
Here is a smaller version of the same thing. Have you ever looked at a child and said he's just like his father, or just like her mother, and meant it as an insult? Think about what that puts on the kid. He didn't pick his parents. None of this is his doing.