Q: Is it worth the effort and cost to challenge an existing Parenting Plan without unbiased evidence but only hearsay?

A: You are going to need to at least invest in a one on one consultation with a family law Attorney. Tell the Attorney everything you know and let the Attorney give you feedback on your case. You need to objectiveness of the Attorney as well as their understanding of the law and the rules of evidence to help you formulate how you would present the case most effectively. Usually one does not put on a child to give testimony but rather hires someone to evaluate the situation and make a recommendation to the court. A professional evaluator is very expensive and will have to make an independent decision based on many factors but part of the evaluation is to interview the child and observe the child interacting with each parent. The evaluator you higher would of course be working for you, so they will try to present the facts favorable to you, but they are independent professionals and they could come to a conclusion that doesn't favor you if the facts point to that. There isn't any way you can get reassurance and cost guarantees via posting on a social medical website and you risk hurting your case because the more detail you post, the more likely that your post will be identified as being from you and used against you in court. Spend the money to talk to an experienced family law Attorney! Paying for a one or two hour consultation is relative cheap compared to what you could spend in a custody battle. An experienced family law Attorney should be able to help you lay out a plan how to gather evidence that you can present to the court when the time comes and thus make the process less expensive.