Q. I feel like my wife is too close to her ex. I realize they are co-parents and must talk about their kids, but I caught her on the phone in the middle of the night chatting with him. We did have a problem with her teenage son, and they said that’s what they were talking about, but talking in the middle of the night seems like crossing the line. I have spoken to my wife about this, and she has adamantly denied that something is going on. What’s good ex-etiquette?

A. You are correct, they must stay in contact with one another because they share children. And it sounds as if there may be some trouble with the kids, so that would dictate the need for conversations. However, I must support you in your concern about middle-of-the-night conversations.

Your first confidant is your spouse — not your ex — and if the problem lies with the child you have with an ex, strict boundaries must be put into place so that your partner continues to feel like your first priority. If they don’t, that’s when I get emails like this one. And it is reflective of the fact that neither of you has conveyed your expectations regarding interaction with a co-parent.

No matter how volatile a breakup is, severing those ties can often be difficult, and parents are not quite sure how to juggle the need to interact with their co-parent. I’ve had clients tell me that they sneak off to talk in private because they didn’t want to upset their current partner.

It is time for a very clear and concise conversation of what is expected in co-parent behavior. Cutesy chats are not appropriate. Neither are middle-of-the-night chats unless there is an emergency, and everyone is meeting at the hospital.

If you are co-parenting, make sure all conversations are about subject matter of which your new partner has been made aware. New partners don’t dictate policy or necessarily weigh in, but they should be aware of any problems so they can support you.

The fewer questions there are between you and your current partner, the more secure you will all feel. That’s good ex-etiquette.

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