Hopefully your parents live a long time and enjoy life.
Concerning POA our Father passed away and fortunately our (5 children) youngest sister took care of everything (she lives in same city the rest other states/countries) sold house etc by POA.
He resided in Florida which at that time required two witnessess. POA
had to be certified (may not be the correct word) by US Embassy. Had to
make two trips from NE to Bangkok. Second trip was because two witnesses were required.
Technically the attorney should have allowed for the Consulate Officer to be