What happens when two sibs that hold power of attny disagree on big issue? Can I contest my siblings actions if I think they are detrimental?

https://www.agingcare.com/questions/poa-revoking-and-rights-of-siblings-469177.htm

You need to keep to one thread. It gets confusing. Already have answers to first one. Will tell Administers about this one so it can be deleted.