AIBU to refuse care for my late dad’s wife?

"her mum ‘raised us’."

But is that true?

She's her stepmother and cared for her 40% of her childhood. True, she had an affair with OP's father which broke up the marriage but that is by the way, really, at this point in time and OP's mother was probably better away from OP's father.

Where are the DCs from stepmum’s first marriage in all of this?

I don't think you are wrong to refuse to help with care. To be honest I don't think it's wrong when grown-up children don't give their own parents care. That being said, I rarely cook for a child that isn't mine, help one with homework, play with or comfort one. If you were with your dad 40% of the time, I find it hard to believe she didn't do these things quite frequently for you, which does mean she had a parent's role with you.

YANBU. Half sister can get carers in for her mum. Ignore.

Well, the estate's heirs are all the children.
OP and siblings step mum may not have seemed warm, but as children they were in her home frequently. Surely, there was some care?
OP has a half sibling whose mum is their step-mum whose home they spent time in.
Yes, they should assist their step-sister.
OP and siblings seem to be holding their father's transgressions against them.

You're not close with your half sister or your dad's wife, so she's looking to use you guys to spread the work and costs. Caregiving is difficult enough for loved ones, your dad's wife is not in that category.

Tell the people contacting you if they're so concerned they should go help out.

Who are these other family members that she is trying to enlist support from and what do they mean to you. More importantly do you actually care what they think? That's the question that's her threat and all that she's got.

I wouldn't provide care for my dad's wife, under any circumstances, and I work in care. My stepdad I absolutely would, we get along really well and he is part of the family, my children adore him and he's like an extra dad. I'm closer with him than my own dad. My dad's wife however I just dislike. She's not a nice person at all, very fake and out for all she can get.

It’s awfully convenient for your half sister that she only ever had two parents to look after. Going by her rationale, that makes you responsible for the care of up to four parents (if your mum remarried). Funny that.

Why shouldn't she be cold? Her dad had an affair with OP's step-mother and left OP's mum when OP was just four. That must have been very difficult for OP's mum.

She owes her step-mother nothing. There is no obligation for adult children to care for their ageing or ill parents, never mind a step-mother who was the reason for OP's parents' marriage ending.

Not unreasonable at all

You are absolutely in the right @AnotherPosterUsername . You do not owe another person care. No one does. Anyone agrees with your half sister and gives you any grief over it, tell them to bob their name on the rota.

Considering you and your siblings also had carers for your own mum, it’s not like it’s unreasonable for the same care for your dad’s wife.

Why is it shitty?
OP didn't choose to have this woman in her life, her dad foisted this woman upon her and her siblings.
Why should OP, whose childhood will undoubtedly have been impacted by her parents separation, now also make her adult life harder for herself by assuming some sort of obligation to her dad's wife?

I dunno I probably would help a bit even just for my half siblings sake.

The half sister didn't live with OPs mum 40% of the time growing up. It isn't the same.

YANBU. Even if she was your biological parent, I don’t believe anyone should have to provide care to anyone else. I won’t be taking care of any of my parents when the times comes because I don’t want to and that is because I don’t have that type of relationship with them. I don’t believe it would be appropriate. If your half sibling is struggling with their mother then they need to reach out to professionals rather than waste their time mouthing off at you. The absolute audacity especially given how your (joint) father and their mother got together in the first place. That would really piss me off.

Tell your half sister that you'll start helping out with her Mam if she agrees to start helping out with yours. I imagine that will shut her up.

It's a rare father who does all the child care, with no expectations of support from the step mum. Frequent threads on here highlight that.
Stepmum may not have been "warm" but I bet she still did plenty.

It is hard enough looking after your own parents when they are old, I’m doing it just now, so do not feel obliged to help someone who isn’t your mum. It’s up to your half sister to deal with it and if you’re not close to her you don’t have to help, she arranges carers to come in when she can’t be there. That’s it really. Your half sis wouldn’t be rushing to help you look after your mum would she?

You aren’t close to the half sister or step mother, I’d leave her to it. I have done a lot of caring for late FIL, late DM, late DSF and given support to late MIL as she died quite quickly rather than needing extensive care. Caring is hard and thankless work and I personally only feel it’s appropriate in situations where you genuinely love the person, they loved and helped you where they could.

I absolutely won’t do it for my father or step monster. Any time me or my siblings have needed any help, major or minor, they have basically sat and laughed. Six holidays a year whilst my DB was at uni unable to afford food. £0 given by them to him. Really do they think he’s going to do caring? Absolutely not.

You reap what you sow.

Nah, you're being cold. Not suggesting you should go and provide intimate care but she was your dad's wife for many years and involved in your upbringing. It's shitty of you not to offer even a small amount of help, if you can. For the sake of your sister, too.

When your half sister made the comment about her mum raising you why didn't you shut it down hard and immediately?

Your mum and dad raised you separately across 2 houses. Your dad just happened to have another woman and child living with him. She didn't raise you.

Yes. You know. Be kind and supportive to their sister.

however the OP has responded to me already, to say they aren’t close to her, so all this is a moot point.