Guardianship vs. adoption rights

[Gibbler]

What is the name of your state?What is the name of your state? IL

Since the age of 2, I was raised by my great aunt and uncle (my grandmother's sister and husband). I am now middle aged and there is much family strife about what is going on with the aunt and uncle as they are in their 90's, living alone, in poor health, and starting to have problems with some dementia.
I have recently found out that the trust they have been making changes to now takes me off as secondary trustee (plus medical decisions to be made), and puts my bio-mom in that position, along with a nephew (who was on there with me previously- he is "first" for trustee).
I have never gotten along well with my bio mom (who voluntarily gave me to my aunt and uncle to raise when she remarried) and am quite suspicious and upset that all of a sudden she is "taking my place", for all these decisions of medical and estate matters. All of these problems seemed to kick into high gear shortly after I moved to another state. Bio mom is very wealthy (due to my stepfather) and has many lawyers at her disposal. My questions is, do I have any legal rights to be involved in decisions made on behalf of my aunt and uncle? They are making these changes to things of great importance when I know that they have times of diminished compacity, sometimes my aunt being outright incoherent. Since I was never legally adopted, but raised by them for virtually my entire life, what am I considered to be in the eyes of the law to them? I feel bio-mom has "pushed" her way into their lives and interferred with my relationship as now that aunt and uncle are in unstable condition physically and mentally she wants to run the show.
Thanks for any help.