To have called time on my marriage. A family of two halves.

No matter how you word it, this is basically what it boils down to. Its a family, and in a family everyone has equal rights - so either everyone has the benefits, or no one. Bringing up older girl knowing she is is a worse position to her sister is cruel. Of course MIL can leave the younger girl money etc but I would stop anything else that is excluding the older girl immediately.

I'm still really weirded out by the OP having another child into a family that treats her eldest like this.

In any case, just another thread demonstrating that "blended families" are shit and do not work.

Why is she vile for only paying for her grandchild’s hobby?

What a god awful situation. I’m nor surprised that you have had enough. What a vile woman your MIL is. I’m so sorry. 🌺

And interestingly enough MIL was wise not to give OP's DH any money - he'd lose at least half of it in divorce now.

I don't see how this situation has arisen. arises. Surely children living in the same house need to be treated the same. The whole thing is being thoroughly mismanaged. The mil has far too much influence. She isn't the parent of any of them.

Yes, she can and should decline... but she has said she won't do that either.

Basically she entered into a very blended family, knowing in advance (from what other posters have said re her previous threads) that her ILs won't financially support her child in the same manner. Then decided to marry and have a child with this man. And now is complaining that exactly what they said would happen will happen.

Sorry hold on I thought the idea was we treat all the children equally or we will fuck them up for life?

Whist I can understand why you feel the way you do, splitting up with your husband isn't going to resolve this particular issue though? His family will still want to treat your youngest in a particular way - and you won't have any control over that. And presumably she will still live with you, and your elder daughter, under the same roof, so there will still be a huge gulf between their life experiences?

but they are children! If I were the MIL there’s no way I would dream of leaving a sister out

Depends. If you take kids to park of course you pay for all ice creams. But I'm not so sure about school fees and e.g. music lessons £50 for an hour.
Also the elephant in the room is if MIL likes OP and her eldest, if she believes her DS is happy with OP etc. We'll never know but OP might be entitled unpleasant women and her DD might be poorly behaved rude teenager and MIL doesn't want to spent her time with them but just being polite when she has to.

I’ve RTFT and I’m a bit confused as to what the actual issue is because to me it seems to be solely about your in-laws money?

Your older DD has her own set of grandparents and you say your DH treats her equally, so why is it anyone’s business what your in-laws do with their grandchildren? Has she not been brought up understanding they’re not her grandparents? How old is she? You mention your DM, so she has a grandmother.

FWIW, I have similar set ups in my extended up (and my own DD has half siblings) and this has never been a thing, because of the understanding of who’s who when it comes to grandparents.

Sorry, what? If the oldest’s father and his parents were around, you’d expect them to treat OPs other child, who is absolutely no relation to them, as well as OPs stepchild, who really really is no relation to them, the same way as they treat OPs eldest child???

What planet do you live on that that seems like a reasonable expectation 😂

But she could decline and explain that her two girls must be treated exactly the same. We had precisely the same situation in our family. My brother's wife had a daughter from a previous relationship and then had two more children with my brother. It was decided at the outset that the stepdaughter would be treated in exactly the same way as as any future children. She was an integral part of my brother's family and thus an integral part of the wider family too. The situation the OP described would never have been allowed to happen. Children have no choice in these cases but the adults do - they can behave well or behave badly. OP's MIL and husband have behaved badly and he's now paying the price.

I think you’ll find the grandmother can ‘cherrypick’ and choose her ‘blood’ granddaughters over an unrelated child, and the ‘honorary granddaughter’ title is irrelevant and fluffy nonsense. Just because her child decided to marry someone with a child by another man, doesn’t mean she needs to jump in and play granny, what a ridiculous suggestion, and has wide ranging implications from hurting her eldest granddaughter, to inheritance. And OPs husband has no say in how his mother treats her grandchildren, particularly as the eldest has a mother of her own. He can’t force her to pay for and bring OPs child to Disney, or force her to pay indefinitely for an expensive hobby for a child she is not related to? Would you have him disadvantage 2 children, including one of his own, just because OPs eldest feels left out? That’s just outrageous.

As far as I can see, this is all on the OP. She was surely with this man for a number of years before she married him. She would have seen the difference in treatment between her daughter, and her future husbands eldest daughter first hand and still chose to marry into this family, have another child and put her eldest daughter in this position.

Im sorry it’s not worked out for you OP, but honestly what did you expect?

I think the problem.is.

Older child. Is not in touch with her paternal grandparents. And Op doesn't earn as much.

Whereas the MIl family are rich as well as the DH first child has a rich mother.

Yes!! And if they couldn’t afford expensive things then 3 cheaper things.

See I just can’t agree with this point of view. I understand MIL isn’t obligated to pay for SD but they are children! If I were the MIL there’s no way I would dream of leaving a sister out, regardless of biology. It’s just a cruel and spiteful thing to do. A step family should mean just that. Family.

Husband sounds like a twat.

Oh. The plot thickens!

I still think the ILs could give some money to their son. It’s hurtful to bypass him completely.

OP’s in laws, and her husband, were very clear prior to the marriage that her daughter was not theirs, and that they didn’t and wouldn’t consider her to be. OP was under no illusions here.

They were never going to be able to be a ‘happy intact family’ in which there was no disparity. That disparity always existed, and will always exist.

The youngest loves her paternal family. Bear in mind she also has a sister on her father’s side she’s close to. She shouldn’t have to miss out because of some misguided notion of ‘fairness’, when the reality is that their familial and financial circumstances are never going to be the same.

But in the future. Is her grandma not allowed to fund her uni fees/ give her a deposit for a house/ or give a large gift for a wedding- in case it breaks the family apart?

And you really think her grandma should do the same for the Stepgrandchild?

As others have said divorce won’t changes things as the ILs will continue to spend money just on kids they are related to.

You don't have the same family build up as op.
Her DH is treating all the girls the same. It's his family that isn't.

You said yourself.

Your DH family don't treat your girls the same as his. You also said this.

The problem would occur if you had a kid with him.

Your DH treats your kids and his all the same. But now his family treats the shared kid between you differently but not your first 2.

And that is the issue here.

You’re being quite unclear OP. Are you saying your in-laws spend money on the children they are related to but not your daughter?

But they're a mangled family.

Youngest is 5. Don't even pretend guilting a 5 year old to give up something she likes because oldest is jealous and resentful is healthy, much less going to keep these people together. They're already separate due to privilege and inequity and resentment.

Eh this is you two the problem not the mil...you clearly say sorry but we won't be doing the hobby because we choose to include all our children in things....your the ones not putting your foot down so all are treated the same and I feel really sorry for oldest

She cannot force her in-laws to spend more on her daughter.