For the sake of this article, I'm going to assume both parents love their children; both parents have good intentions for their children; both parents want to see their children succeed in life. While that's not every case, it's not a far-fetched idea. But…
This is family court we are talking about here, so we know that there is a pending problem. There is a disagreement among the parents, a fundamental disagreement. Not just a disagreement about whether the child should be allowed to wear pajama bottoms to class. (Although I can think of few parents where that idea may cause WWIII).
Well-meaning, involved parents can disagree about which school the child should attend, whether the child should be vaccinated, will the child be allowed to play rough contact sports, whether the child needs therapy, even how to care for a special needs child.
A well-drafted parenting plan considers the possibility of parents disagreeing over issues on education, health, social and religious activity. Even people in the friendliest of divorces must anticipate what could happen if things go wrong.
Parents who do their own paperwork, or who hire non-lawyers to draft paperwork and give non-legal advice tend to gloss over these issues. "Blah, blah" "Yeah, yeah" "We know what we are doing, we don't need to write it down." Until… someone says, "It's my child and I'm doing it MY WAY!"
The communication may sound like a sweet Frank Sinatra song or the other party may be using the hammer and dynamite method; WWIII may be imminent. If one parent says, "It's my child, my way" your sparse, barely filled in and ill-contemplated parenting plan is of no help.
Then, of course, there are those parties who do have a court order and for some reason, no one is following the order. Both parties are on the freeway, riding top down, singing — "Control" (cue Janet Jackson). Until… someone decides to take a detour. It's always been one way, and now the parties have veered off the highway. Perhaps one party now says, "We have a court order, remember!"
When well-meaning parents are demanding their own way, it can cause the other parent to shrink back, to be less involved, to be a less responsible parent. And while not having an argument among the parents is a good goal, communicating to the other parent that their decisions and opinions are not valid or important can have serious repercussions, not only for the parents but the child too.
Telling the other parent they can "take it or leave it" — don't be surprised if they hit the highway, or… bring this matter back to court. I've seen the court hand out consequences such as appointing a Guardian to monitor the parents and the child, awarding a change in majority time sharing and even ordering that the party who won't follow the court order pay the attorney fees for the other parent. That Frank Sinatra song may have you paying the costs in more ways than one.
My advice: Take the time to prepare a good parenting plan, one that considers the ages and stages of the child. If there are disagreements don't isolate the other parent — listen, communicate, mediate, come to a rational agreement. If you insist on demanding your way, make sure it's backed by a court order.