Are Text Messages From A Stolen Phone Admissable In Court?

Location: Michigan

So recently my ex hasnt been showing up for visitation. I've filed multiple denials of parenting time, and waiting on the court to do something about it.

This summer my ex stole my mother's phone, and gained access to all of her text messages, Cashapp account, etc.

My ex read through about 2 years of text messages between my mother and I. Some of them were very personal, talking about family fights, talking about my depression, arguing with each other. Some of the messages were from me saying how stressed I get when my son comes to visit. How much anxiety it causes me to deal with his mother.

Anyways. I got a call and a visit from CPS and they said very sternly that I need to get a hold on my anxiety, and I agree. I had already started seeing a counselor, and my doctor made a change in my medication that seems to be helping. They were very clear that if I don't get a hold of my anxiety that I could lose my visitation rights. I promised to follow through with counseling and to do better, and he said he was closing the case.

So yesterday I asked my ex if she was going to show up to visitation and she said no, because she has to talk to her lawyer. She said they are responding to the parenting time denials "with the facts", and that her lawyer is requesting a modification of parenting time. I don't know if this is true because she often threatens stuff like this.

My question is if she does follow through and request a modification of parenting time, are these text messages from my mother's stolen phone going to be admissable in court?

I do have anxiety, and sometimes my mother and I argue just like any other family. As you could probably imagine, if somebody anybody's texts for two years, there's probably some damning, or embarrassing messages in there. I've never hit my kid or anything like that. They mostly just mentioned me and my mother arguing, and how my anxiety could affect my relationship with my son.

I'm going to do everything I can to curb my anxiety and be a happier person when he's a round. But am I at risk of losing my visitation rights? I'm scared to death. I miss him so much. It's been 2 months since I've seen him or heard his voice, and I missed his 13th birthday. Any advice and support is appreciated. I do plan on getting an attorney if it comes down to going to court.

TL:DR Are text messages from a stolen phone admissable in a FOC hearing?