Hello SeekingAnswers: Thank you for bringing your concern here to PC. Since this is your first post... welcome to Psych Central.

I don't believe there is any help I can offer with regard to your concern. However here are links to 8 articles, from Psych Central's archives, that (hopefully) may be of some help:

10 Strategies for Dealing with Your Narcissistic Ex | The Exhausted Woman

7 Ways Narcissists Retaliate Through Children | The Exhausted Woman

How to help your children when their other parent is a narcissist

When Your Kids Turn Against You In Favor of the Narcissistic Parent

Narcissists Do Not Parent: This Explains Why You are Having Such a Hard Time!

https://pro.psychcentral.com/recover...-co-parenting/

https://pro.psychcentral.com/recover...dium=popular17

https://blogs.psychcentral.com/narci...dium=popular17

I hope you find PC to be of benefit.