05/07/2013 05:24 pm ET Updated Jul 07, 2013

My Husband's Kids Are Coming to Live With Us!

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When we interviewed women for our book Love for Grown-Ups, a relationship guide for women who marry or re-marry over the age of 35, many of these women (including all three authors of our book!) married men who already had children. If the children were living with their mom it was assumed that's how it would always be, but occasionally they discovered that a small bomb-shell was dropped into their lives when the kids they liked very much (but didn't have to pick up after!) moved in.

These life-changing situations are never easy. There may be a million different reasons for this new set-up: maybe your husband's ex-wife is re-marrying and his son or daughter doesn't get on with the new step-father to-be, or maybe she is moving out of state and your husband won't allow the children to go with her, maybe one kid or more has decided that living with you will be easier than continuing to live with their mom. Regardless of the reason, your life and the kids' lives are about to make a major change.

You may be angry about the situation, but don't be angry with the kids. Trust us, blaming the kids caught in the middle of this situation won't help. There are times we say you have to take a "grown-up pill" and this is one of them. His kids are coming to stay and it's best to try and make it as easy a transition as possible.

Is Dad a "softie"? Often a dad will feel guilty about breaking up a marriage and thereby changing the lives of his children. No matter how much he realizes that raising a child in a home where there is constant squabbling is not good, he may still feel emotionally torn so make sure to have a long heart-to-heart talk with him about the new family routine before the child moves in.

How will this change affect your children or "our" children? Before his child (or children in some cases) move in there are important logistical realities to be worked out. Do rooms have to be shared? If they're ages are very different how will you regulate TV time? Can you afford a second TV? What about computers? How much do the kids have to be driven to activities and who is going to do that? If your kid has to get to a ballet class and his has a soccer game, how can you manage it? If you're a working mom what's your access to child care or baby-sitters? Is the child old enough to be left alone in the home after school?

Lay the ground rules. Discuss with your husband what responsibilities your step-child will have in their new home. Will he or she be expected to make their own beds, set the dinner table, help with the dishes, etc.? Avoid resentment and make sure responsibilities are equally divided between your children and your step-children. Don't become "the wicked stepmother."

It's their home now. This is important to remember. You don't want to treat them as temporary guests nor do they want you to. You have become an extended family and they're part of it. You have to be emotionally available to all the children in your life. If it wasn't their choice to move in with you they may feel sad and resentful. Your kids may feel that they're being shut out or ignored- be sensitive to the fact that this is a challenging time for everyone.

They have rights too! Teenagers are going to play their music (at an ear-splitting level), want to have their friends over, want to hold parties, etc. All these things have to be incorporated into your new life, but that's why it's important that you should plan and discuss these ahead of time so you're not scrambling for solutions when these things come up (and they will!).

Look ahead and take a breath. Remember, children do grow up and eventually leave home. Many of the women we interviewed admitted they missed the kids when they finally moved out for the last time. You and your husband hopefully will have plenty of alone time together in the future. You will need to establish a relationship with the children that works for all of you -- but you're the adult. Be flexible. You aren't their mother, but you can be a loving, caring adult in their lives, one they always knows they can turn to.

How would you react if you found out your step-children were moving in?

Ann Blumenthal Jacobs, Patricia Ryan Lampl and Tish Rabe are the authors of Love for Grown-ups: The Garter Brides' Guide to Marrying for Life When You've Already Got a Life, a relationship guide based on interviews with women who married over the age of 35. The book tells you how to find Mr. Right, marry and find life-long happiness. The Garter Brides are a sisterhood of women who all got married later in life. They offer tried and true advice on how to have the love and life you want.