This is a story about how quickly parents, if they are determined enough, can make significant change in parenting policy.

The family in question consists of two boys, ages 9 and 8, and a 12-year-old girl. Mom admits to having centered her existence around her kids. She describes herself as a “too big to fail mom.” She was a mom who felt she had to do everything for her kids, which may have had something to do with the fact that Dad travels a great deal.

Early on, Mom began allowing the kids to sleep with her when Dad was on the road. Within a short time, as usually happens in such situations, the kids were sleeping in the parents’ bed when Dad was home.

Since the bed isn’t big enough for five people, the kids took turns. Two of them would crawl into bed with Mom and Dad and one would sleep on the bedroom sofa.

Then the parents attended one of my two-day small-group seminars. They didn’t feel they had any particular problems, mind you. They came because they thought it might be interesting.

At the end of the first day, during which I devote a good amount of time to the need for a boundary between parents and children, they decided that they had some problems after all. The kids were obedient, well-mannered, and did well in school. Nonetheless, and almost literally, there was a gorilla in the room.

Those of you who’ve followed this column over the years know that I do not approve of kids being in their parents’ bed, the exception being when a young child is ill and needs constant monitoring.

But healthy kids should not be in mom and dad’s bed. Or, in the case of single parents, mom’s bed or dad’s bed. The parents’ bed is Boundary Number One. If that boundary is not enforced, parents are going to pay the devil establishing any other boundary, physical or emotional.

So, Mom and Dad decided to put an end to it. And in one night, they did. There was no transitional period to help the children adjust or any other such nonsense. After dinner on the evening of day one of the seminar, they sat the kids down and said, “You are not sleeping in our bedroom ever again. You have your own bedrooms and beds and that’s where you’re sleeping. And if you come into our room in the middle of the night, you will be sent or taken back out.”

The older of the two boys asked if they were going to leave their door open, to which our formerly Too Big To Fail Mom said, “Maybe and maybe not. If it’s open and you come in without an invitation, you will be sent back out.”

That night, the kids fell asleep in their own beds and woke up the next morning in their own beds. And they were not acting traumatized, which is what attachment parenting babble would have you believe is going to happen.

The parents have their marriage back. The kids, because they are no longer quasi-members of the wedding, have their childhoods back. Win-win!

This is what can happen when parents get on the same page and take action. Under those circumstances, it does not take long for action to produce the proper reaction.

Family psychologist John Rosemond: johnrosemond.com, parentguru.com.