When you share children with a person, you aren’t going to be done with that person until the children are adults. Even then, you might still have to communicate with them. One thing that you shouldn’t ever fall into the habit of doing is using the children as messengers between the adults in the situation.
Many parents try to send messages to the other parent through the children, but this is a recipe for disaster in many ways. First, the message might not be relayed in the intended manner. It might become skewed because the child doesn’t repeat it as stated. Your child might also feel like they are stuck in the middle of a conflict if they are giving messages back and forth.
Using your kids as messengers goes far beyond just having them relay messages between you and your ex. You also shouldn’t ask the children to report the things that are going on at the other home. While it is understandable that you want your children to relay their experiences, don’t have them do this for malicious reasons.
You also can’t try to have your children mimic your displeasure. You and your co-parent should have a united parenting front so that the children know they can’t play one parent against the other. Without this, the children might think that they can get one parent to agree to something that goes against what the other one has already issued a decision about.
Having communication terms included in the parenting plan is beneficial so that both parents know exactly what’s permissible.