Man refuses to cut off 'disgusting' dad for half siblings, 'they gave me an ultimatum.' AITA?

"AITA for telling my half siblings I won't drop my dad for them?"

When I (24m) was 7 my mom died. I had two younger half siblings who were 4 and 3 at the time. They had different dad's. The older of my two half siblings was born as the result of an affair mom had while she was married to dad.

He found out about the affair before mom gave birth and got a DNA test so he didn't have to be responsible for the baby. He had to do the same again because mom got pregnant again before the divorce was finalized and had to prove he wasn't the father.

It was apparently a really big fight because she wanted him to raise the three of us and he said never. My mom had primary custody of me and full custody of my half siblings because neither had their dad in the picture.

When mom died, I went to live with dad and they were separated from each other and placed apart. I never saw them for the rest of our childhoods. But eventually, as I learned, our mom's family were found and took them both in. They had no idea we existed.

They reached out to me last year. We talked some. They told me about mom's family. They asked about my life. It was going okay between us for a while. But then they started to tell me my dad was an ahole and how dare he let them go into foster care, how he was responsible for separating us and they told me I shouldn't have anything more to do with him.

They didn't like that I was close with my dad. I said we needed to drop that line of conversation, but they wouldn't. They said he should never have allowed us to be separated and a real man would have taken them on when they had nobody else.

The time they were in foster care was shitty and they've opened up about it. They blame my dad for it. But even if it makes me an ahole, I don't. He's not their father and wasn't in their lives when mom was alive.

I tried to keep building a relationship with them but when they gave me an ultimatum I told them I won't drop dad for them. They said I should go to h$ll and think about what a disgusting POS I was standing by. AITA?

Here's what top commenters had to say about this one:

Newbosterone said:

NTA. Why are you even asking? Perhaps if your half-siblings are cheated on, they will understand better. Their situation is the responsibility of their mother and her affair partners, not your dad.

angeIbbunnie said:

NTA. Your dad wasn’t their parent, and it’s unfair for them to put all the blame on him. It sucks they had a rough childhood, but that’s not your dad’s fault, and you shouldn’t have to cut him off for their sake. That’s toxic.

Huge_Mistake_3139 said:

NTA - Sounds like your mom’s family has been resentful for years and planted those thoughts in their head. How dare they even try to give you an ultimatum. Sorry things didn’t work out for you in this reconnecting. Your dad did step up and take care of his responsibilities, which were you.

SeaworthinessDue8650 said:

NTA. I understand why your father didn't take them in and I can't blame him. Have they tried looking for THEIR fathers?

DragonessFlame said:

NTA. Your dad was already dealing with enough drama for a telenovela, and your mom wanted him to take on BONUS KIDS that weren’t his? Nah. That’s not how any of this works. The fact he stepped up for YOU and gave you a stable home says a lot. I say your dad is a champion!

quirkytypeofteacher said:

NTA. Your father had no obligation to raise them. It's not your fault or his. Your mom made her choice, and she didn't have a LEGAL plan for the 3 of you to keep you together if anything were to happen to her.