I can't find the PP who quoted me as snippets of my previous comment have been mentioned by a few.
But I think fundamentally it comes down to the fact that I view stepchildren as members of my family unit. And I think they warrant the same treatment as biological children.
I've said, twice now, that of course it would be preferable if they could stay with their mum. I'm sure they're probably prefer that too (we don't actually know that but it's a very reasonable assumption).
But if for any reason that wasn't actually possible, I don't think it's a strange request for the step-parent to look after the children in the father's absence. It's his contact time, I think it's perfectly reasonable for the step-parent to pick up the care - because it's a blended family and I believe quite strongly that's the right dynamic. Obviously a subjective opinion but one that is very heartfelt for me.
I completely accept that it would be difficult because he is in hospital and OP has enough to be thinking about. Hence why I said it would be preferable for the mum to have them. But unless I've missed a post from OP we know nothing about her reasons or her circumstances.
Presumably OP and DH would have been having the children anyway, so surely nothing would actually need to change if she had them? Unless OP is completely hands off and has nothing to do with the stepchildren at all? Which might well be the case but for these children who live there 50% of the time, I think that would be really sad.
I also think if a woman posted on here that her ex was ill and was expecting her to look after the DC during his contact time, and that she had no childcare and needed to work, the answers here would be very, very different. I think women can be wonderful in looking out for each other because we do get a shitty deal in society, as a whole. But I also think that sometimes skews our perspective. I find MN tends to be very protective of step mums and encourages a hands off approach - but that doesn't mirror any of the dynamics of blended families that I have experience of in real life. It would be really interesting to see what the responses would have been if the mum had posted - I very much suspect she would have received a lot of support and understanding, and people would be saying the childcare is up to the ex to sort out.
As I said above, to me stepchildren are part of my family unit, and I wouldn't be with a long-term partner who didn't view them in the same way. Especially when those children are in the home 50% of the time as is the case with the OP here.
I am guessing the PP who are saying the OP should wash her hands of this issue don't view stepchildren as part of the family unit. And that's fine, but that wouldn't ever sit right with me - hence the difference in opinion. Because you wouldn't treat your own DC that way, and personally I don't think there should be a differential - all of the children within the family unit deserve the same treatment.
Ideally the OP and the mum would have a conversation and come to an agreement but the OP doesn't seem to like the mum very much. As I said before, I'm guessing there's some kind of back story that we don't know.