AITA for refusing free dental work to my financially struggling family members?

I'm an orthodontist, 35, married to a wonderful woman, 33. Her family's always been great, but I recently had to set a boundary.

My brother-in-law asked me to do free orthodontic work for his kids. I told him I couldn't, that I don't do free treatments, even for family.

He got upset, saying I'm selfish and greedy because I'm successful. He made snide comments about doctors making a lot of money. When he said "What's a few thousand dollars to you?" I told him my bank account isn't a piggy bank for family members.

I explained it's about principle - fairness and consistency in my practice. Waiving fees for family would mess that up. It wouldn't be fair to my other patients who pay full price.

To be honest, my brother-in-law's family is struggling financially, and it's hard to see them dealing with that. But I still can't justify giving them free treatment.

My wife agrees with me, but she's really torn up about the whole thing. She's sad that her brother's being so critical and that it's causing tension between us. It's taking a toll on her, and that bothers me more than his entitlement. I'm frustrated he's dragging her into this.

To make things worse, even my in-laws are chiming in. My mother-in-law and father-in-law keep telling me I'm being unfair and that family should come first. They say I should "help out" since we're financially stable. But I don't think that's reasonable.

To clarify, I'd help with discounts or payment plans, but free treatment? No.

For the record, no free treatments - not even for my own family.

AITA?