Q. My ex and I split up six months ago and our children go back and forth between our new homes. We don’t have a formal parenting plan — the split was amicable; we just share the kids every few days. They are 5 and 7. It seems to be working OK, but I have recently met someone new. I am afraid this will complicate things, and their mother will not return the kids when I want them. What’s good ex-etiquette?

A. The introduction of a new love interest, especially after only 6 months of living apart, means a new person will probably come as a surprise. So you are right about being a little concerned. Hopefully, if your ex is triggered, she will not use the children to get back at you. The kids are probably confused as it is, since no one can project where they will sleep on a regular basis.

Having a formal parenting plan in place is a good idea for multiple reasons.

First, a parenting plan allows co-parents to plan their life, plus adds consistency to the children’s transition from house to house. The kids will know where they will be, and so will their friends and teachers. Consistency will help your children adjust to the fact that they now live in two homes.

Second, it will prevent arguments. There will not have to be a discussion and the need to negotiate each time there is a transition.

So, how do you break the news that you are now seeing someone else? Is it even necessary to tell your ex? Won’t the kids just say something, and you won’t have to deal with it?

The kids probably will — and that’s the problem.

If mom has no idea that you are seeing someone, when the kids come home with the news, her reaction could easily be over-the-top. Say she loses her temper and acts like it’s all wrong. Now the kids think you are doing something wrong, when meeting someone new is completely predictable.

That’s why it is best to tell your co-parent before the kids know, even if it is as insignificant as, “I’m dating other people now.”

The kids now know you talk, can problem solve, and it’s OK to like the new partner. That’s good ex-etiquette.

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