Q: My ex and I have a son and have been trying to co-parent for five years. There have been ups and downs — she was resentful that I did not suggest marriage, but we hardly knew each other and I didn't think that would be the answer.

Things have gotten really bad since I got married last year and my wife is now pregnant. The exchanges are hostile with my ex yelling obscenities at my wife in front of our son. Now my son says he doesn't want to go back to his mother. What's good ex-etiquette?

A: Certainly not fighting in front of your child, that's for sure. But, let me digress and explain your child's reaction. Experience tells me it's not his mom he doesn't want to see, it's the fighting at exchanges. Being only 5, he can't explain himself, so when it's time to return to Mom's and exchanges are hostile, he simply says, "I don't want to go" or starts to cry.

You see that and think it's got to be he doesn't want to return to Mom. However, connect the dots. If he's been fine with Mom over the years, the exchanges have recently gotten more hostile, and all of a sudden he's dragging his feet when it's time to go back, he's probably not afraid of Mom. He's afraid of how she — or all the adults — act at the exchanges.

Put yourself in the other parent's shoes if problem solving is difficult. Doing that, it's easy to understand why your son's mom is acting that way — she's upset that you wouldn't marry her when she was pregnant, you married someone else and now you are having a child.

But that's not your child's problem. All he knows is Mommy and Daddy (and possibly Daddy's wife) are angry with each other — and if he's like a lot of children in his position, he personalizes the anger and thinks it's because of him. So now you have this little guy stuck in the middle of a lot of drama he can't possibly understand — and blaming himself.

Granted, we all get why Mom is angry and hurt, but it doesn't matter. It's about your child. There's now proven research that it's detrimental to children when parents continue to fight after a breakup. Aside from the obvious psychological impact, children can experience physiological reactions related to stress that may actually harm brain development.

Think about enlisting the help of a counselor or co-parenting class for tools. Try to cut down on parental interaction and consider curbside exchange (delivering parent stays in the car and the other parent stays in the home and the child walks from the car to the home) or making the exchanges to and from school.

Just make whatever changes need to be made — and do it fast — in the best interest of your child.

Jann Blackstone is the author of "Ex-etiquette for Parents: Good Behavior After Divorce or Separation" and the founder of bonusfamilies.com.