Serving as Power of Attorney for a sibling — a brother or sister who’s ill, disabled, or aging — is an act of deep trust. The legal duties are the same as for any agent, but the family dynamics can make it more delicate. Here’s how to do it well.
The duties don’t change
Whoever the principal is, an agent must act only in their best interest, stay within the document, keep the principal’s money separate, and keep clear records. Being family doesn’t lower the bar — if anything, it raises the importance of transparency.
The dynamic that does change: other siblings
When one sibling holds the Power of Attorney, others can feel left out or suspicious, even with the best intentions all around. This is where many families fracture. The antidote is communication and records:
- Keep other close family reasonably informed about big decisions (without violating your sibling’s privacy or wishes).
- Document everything, so questions are answered by a clean record instead of a defensive conversation.
- Remember your duty runs to the principal — your sibling — not to keeping every relative happy.
When a sibling is the problem
Sometimes the concern runs the other way: a sibling who holds the Power of Attorney is misusing it. If that’s what you’re seeing, learn the signs of a sibling abusing a Power of Attorney and the red flags of financial abuse — and act.
Get it set up right
Your sibling grants the Power of Attorney to you while they still have capacity, using a valid form for their state. The POA Handbook covers the how, and the POA Caregiver Program prepares you for the role that follows.
_This article is plain-English education, not legal advice. Power of Attorney law varies by state, and reading it does not create an attorney–client relationship. For guidance on your specific situation, talk with a licensed attorney in your state._