From your description of the facts, there is no conflict of interest. It would be a conflict of interest here if, for example, he had represented you in the divorce and now, in a different proceeding, he represented your ex-husband.
Also, from what you say, the hearings you are a part of are in open court. Thus, anyone has a right to attend, so your ex-mother in law is well within her rights to be present.
Hopefully you have a good attorney on your side for these proceedings.
Felipe Fulgencio, Esq.
I agree with the above answer, that from the facts you provided, it is not a conflict of interest. The court is open to the public, but I am not sure what kind of mediation(s) you have been having or how many. I think if you were uncomfortable with that, you could have asked the mediator the the attorney to have her leave. A mediation is not a public hearing.
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