By Jann Blackstone

Q How do you suggest I deal with a lying ex? We were at our child exchange and I hear him telling our child a story that was such a lie. I had to stop him and set the record straight, but it turned into a crazy fight. Our children were crying, my ex was mad. What’s good ex-etiquette?

A First, no discussions about anything important at child exchanges. Keep it light and cordial. When I tell co-parents this, I often get, “But it’s the only time we see each other. When do you suggest we keep each other informed about the kids?”

Any other time than exchanges. Exchanges are not for comparing notes or calling each other’s attention to something that was not done to your liking. Exchanges are for exchanging the kids. Period.

If your interactions with your co-parent are just too volatile, make an appointment to chat when the kids are not around. Choose a casual public setting — not one of your homes. Have a plan for what you will say and always come to the table with a suggested solution.

Stay away from calling your co-parent a liar.

Seeing something from a different perspective does not mean they are lying and being called a liar has a tendency to send the conversation into a spiral; even if your co-parent is lying, they will immediately go on the defensive and little will be accomplished.

You can question somebody’s motivation without calling them a liar. Try something as simple as, “I have a different perspective.” Or, “I see if differently.”

Although I am not a proponent of co-parenting via text, if things are so chaotic that you can’t speak to one another, passing on important information through writing may be the best alternative for now. I prefer email to text.

Remember, every conversation you have with your co-parent, spoken or written, sets the stage for the next conversation. You won’t be the loser if you’re the first one to stop the negative back and forth. However, your children will be the winners. That’s good ex-etiquette.

Dr. Jann Blackstone is a child custody mediator and the author of “The Bonus Family Handbook.”/Tribune News Service