Upset, I think you really need to tell us the whole story.
As POA, you are appointed by your loved one to do what they ask you to do while they are competent. You really have no obligation, as I understand, to keep your siblings informed, but sometimes if there is mistrust or idiocy on the other side, it can be prudent, after consulting a lawyer, to divulge what you need to .
If the sibling is calling APS, present your paperwork and reciepts to APS. APS has the duty to investigate and to make sure that there is no financial abuse.
Document everything you do for your dad and I would send out weekly updates so your family knows everything you do, how much work it is, and what a pain it is to be POA.
As POA, you are appointed by your loved one to do what they ask you to do while they are competent. You really have no obligation, as I understand, to keep your siblings informed, but sometimes if there is mistrust or idiocy on the other side, it can be prudent, after consulting a lawyer, to divulge what you need to .
If the sibling is calling APS, present your paperwork and reciepts to APS. APS has the duty to investigate and to make sure that there is no financial abuse.