Our client's son has a durable power of attorney for his mother, but not for his father. All of the accounts are held jointly by both husband and wife (and in Florida that is assumed to be Tenants by the entireties). The son has requested that some of the accounts be closed and has presented a copy of the POA as documentation supporting his authority to act on behalf of his mother. Can the son act on a joint account based on the POA, even if he is not an attorney-in-fact for the other party on the account?