1) You can fire her lawyer from representing her, so long as she (your friend) does not overrule you and decide to keep the lawyer: while you can act for her, given the POA, you cannot overrule the specific wishes of the person who gave you the POA.2) You cannot however directly remove the lawer from being adminsrator of or doing legal work for her grandmother's estate, since that lawyer does not work for your friend: he represents the estate, and your POA from your friend gives you no power over the grandmother's estate.3) You could, however, bring a legal challenge in court, on behalf of your friend (as her POA)--again, so long as she does not specifically disagree and say to not do this--against how the adminstrator is managing the estate: any heir or beneficiary, and so an heir's or beneficiary's POA on her behalf can do this. This kind of legal action is traditionally called an action "for an accounting" and the adminstrator is forced to "account" for his management of the estate: i.e. to show that he is following the will and/or the law (like the law for "intestate succession," or who gets what when there is no will), is being careful, is being loyal to the beneficiaries' interests, and is not engaging in "self dealing," or benefiting himself at the beneficiaries' expense. If a court feels the administrator is mismanaging the estate or beng disloyal, the court can order him to do--or not do--certain things, to repay amounts wrongfully taken from the estate or spent from estate money--or replace him as administrator.This type of legal action is complex for a layperson. You are advised to consult with a probate attorney.