Can the guardian be different from the DPOA and which one "trumps" the other?

Co-guardianship -- and DPOA? Me and a sibling are listed for medical with regard to my mother's dpoa, the other sections list me -- some siblings don't agree with this arrangement and have threatened to contest it in court -- how long/expensive of a procedure is that ?? they want to waste all this energy and money and in the end, nobody wins.....
anyway, they have threatened to apply for guardianship of both my mother & father, what kind of procedure is this and what if all siblings are not in agreement? some of my siblings are meeting with an elder law attorney, a last minute meeting that i cannot attend in person, (maybe conferenced in), is co-guardianship a good option?? guessing this means only 2 people, right??