AITA for not wanting to pay for my stepkid's education despite paying for my own kid?

15,812 points3,003 commentssubmitted by Gloomy_Business to r/AmItheAsshole2

My husband and I have one daughter, age 7, and he has two older sons from a previous marriage (11 and 15). They currently live with us but had been living with his mom up until about 2 years ago. Their mom is really messed up, addicted to drugs now and on the brink of death basically due to her addictions. My husband has largely cut ties with his ex-wife but is obviously still responsible for his sons.

So here's my current dilemma: I want to send my daughter to private school, starting next year. It'll be expensive, like 15k a year, but I've talked to my husband and we can spare the money because we want our daughter to get a top-tier education. However, a few weeks ago my husband confronted me about potentially paying for his younger son's schooling as well. His oldest being in high school already is uninterested in switching schools but his younger son is apparently not opposed to the idea. I was upset because he told his son this without even telling me.

Between our salaries, we can only really afford one kid to go to a 15k/year school. I'm a bit upset because sending our daughter to private was always part of the plan, and yet my husband just casually floated the idea to his son only for him to say "ok sure." And now that we've done the math we realize that we can't at all afford 30k on tuition. I still want to send my daughter to that school because we've promised her so since she was about 5, but my husband says either both kids go or neither does. I feel like he's intentionally sabotaging our daughter's chances and it's making me really upset. However I get that he wants the best for his kid as well but I resent how casually it was raised and how his son responded so casually to his dad's question.

I want to issue an ultimatum to my husband. Basically we pay for our daughter's schooling first and foremost because we made the promise to her first, and I want my husband to tell his son the bad news because he was the one that promised him something neither of us could deliver. AITA for thinking this is a good plan?