Q: My 13-year-old daughter came home from her father's with magenta hair. She asked me if she could dye it last week and I said no — but her father let her do it, and I'm furious. What's good ex-etiquette?

A: "Hair" becomes a huge deal for parents who share custody, particularly for moms. I can't tell you how many complaints I've heard — from moms who are furious that Dad gave Junior his first haircut to the example you gave. Best bet, when the children are small, decide who will be in charge of personal grooming and stick to it. A good rule of thumb: Don't make a decision about haircuts or hair color unless notifying the other parent before you do anything.

I have to admit, I have run into this problem myself. When my daughter was around 14, she came back from Dad's home with Bozo orange hair. It wasn't so much the hair color, although the color was hideous, it was the fact that I had said no previously — and didn't tell her dad about the conversation because I thought "no" would be the end of it. But my daughter, 14 and feeling all about herself, decided it was OK if her father said it was OK, went to her father's, dyed her hair, then came home very proud that she got exactly what she wanted.

Unknowingly, her father had undermined me simply because he did not call to check. I set myself up for failure because I didn't keep Dad in the loop that our daughter was lobbying for orange hair.

Most of the time, these kinds of problems boil down to communication. And, don't ask the child if they asked their parent if it is OK — you ask their parent. Try something like, "Our daughter is talking about dyeing her hair orange. I told her no. I hope you will support me on this."

The reason you are facing this problem is because you and Dad do not compare notes, and hair color is just the tip of the iceberg. Most parents start to back off when their kids hit middle school because they think their child is getting older and can handle a little responsibility. However, as a child gets older, that's when parents really have to stay on the same page, otherwise you will find yourself saying yes to a sleepover thinking they will be at the other parent's when they really are somewhere they shouldn't be. And, if you think your child would never do that? When Mom and Dad don't check in with each other, that's leaving the door wide open for all sorts of dangerous experimentation.

One of the key things one can do to improve communication between parents and bonusparents is to ask their opinion. Dad or Mom may have another take that you didn't see — and truly listening to someone's opinion is a step toward compromise. Hear each other out before the final decision is made.

Try something like, "So, what do you think about our daughter dyeing her hair orange?" If he says it's OK, a good trick is to tell him you'll consent only if he dyes his hair the same color. Nine times out of 10 that works. Then there's that one parent who will say, "Sure," and likes the idea. That explains a lot, particularly why they are an ex. You lost that battle before it started. Pick your fights. That's good ex-etiquette.