Q: My ex and I have been divorced for five years. We share custody of our two kids, ages 10 and 11. The kids spend a week at my house and a week at his. We have co-parented really well together — until recently. He just got married, and she's taking over.

For example, I pick the kids up every day after school, and he comes to get them after work on his weeks. Now that they are married she picks them up from school on his weeks and I don't see them for a week! She's changing everything and is acting like their mother, and it's really making me angry. This can't be good ex-etiquette!

A: What's not good ex-etiquette is not that she's picking the kids up after school, but that you and your ex didn't have the conversation about how things would change once he married. Good ex-etiquette means that neither of you should be surprised by anything — everything should have all been discussed well in advance so that you can all appear as a united front for the kids in your care. It's not an easy conversation, especially if it feels like she's taking over, but from what you described, she's really not.

On paper you and your children's father shared equal custody, a week with you, a week with him. You made a separate arrangement to take care of the kids after school until he gets home — and that's the way it should be, parents helping each other with the kids. But he no longer needs your help because his wife is home, and it's upsetting your previous arrangement, but she's not necessarily taking over.

It's not uncommon for the custodial parent to be responsible for day care when the children are with him or her. The transition certainly would have been easier if you would have known what to expect. If a week is too long between visits, I suggest a dinner visit in the middle of the week, just to touch base.

Now let's address your concern that this woman is trying to take over and acting like your children's mother. It's naive to think that someone who lives with your child half the time is not going to have an influence on them — and she will probably perform mother-like duties for your children. However, that does not make her their mother, nor will they think that she is their mother.

Rather than be intimidated or angry about the situation, stop comparing and get to know her. The more you two cooperate, the more secure your children will be and the more they will feel comfortable going back and forth between your homes. Give them permission to form loving relationships with all the parental figures in their lives and they will.

If you make it difficult on them or force them to choose, you may be disappointed if you are the one instigating the chaos. Remember good ex-etiquette for parents rule 3, "Don't bad-mouth." Badmouthing someone your child cares for, whether it's a parent, bonusparent or even a friend, backfires.

E-mail Dr. Jann Blackstone at drjannblackstone@gmail.com.