My question involves estate proceedings in the state of: PA

Mom and Dad are elderly. Mom has dementia, and is not competent. Dad is mentally OK. For now, since Dad is alive and OK, I am guessing that he needs power of attorney over my Mom? For example, their mutual assets (such as their house) would be under the the exclusive control of my dad?

Also, would like for the power of attorney to convert to one of the children if my Dad dies before my Mom.

How does this work? What is involved?

We are looking to retain an attorney, but I wanted some general info before we contact someone, and not go into it completely in the dark. Thanks.