Would this upset you?

[PickAPatter]

If you had children from a previous relationship and a child with your current spouse and you heard a telephone call between your spouse and their parents asking if they could meet at a local attraction at some point soon but specifically asking not to bring your older children so they could spend some time with their grandchild.

We tend to do lots together so the older kids tend to come along a lot when we meet with spouses parents. Older kids really like spouses parents too although don't call them grandparents.

They were 4 & 6 when we met.

YABU - there's nothing hurtful in this conversation.

YANBU - I'd be hurt and would say something.

I have always believed this and always will. You and your husband went into this marriage knowing you had kids from a previous relationship. Those are just as much his kids as they are yours and it's not right that his parents want to spend time with "HIS biological" child. This is setting them up to be treat different from the get go. Your kids from the previous relationship will grow up seeing THAT child as the he favorite or golden child to them. I would put a stop to that now. You aren't wrong. The GPs are.

You and your husband went into this marriage knowing you had kids from a previous relationship.

Their parents didn't though.

(I.e. they made no commitment at all)

Not even all step parents feel that way, so why would you expect step grandparents to do do?
The dc don't refer to them as grandparents so they recognise the difference in relationship.

As someone who's father remarried (i.e. I had a stepmum and step siblings) and can confidently say that this might be true for some families but not all.

In fact the concept of being just as much my stepmum's child as my biological father's child is totally alien to me (and I can't imagine my mother being too happy about it), let alone her parents considering me their grandchild. Appreciate this won't be everyone's experience but it was definitely mine.

*I can confidently say.

My sister has a stepchild. He came into her life when he was 4, I met him closer to 5 when things got more serious - she got pregnant soon after. Honestly, he’s a nice kid but I don’t view him as a nephew. I buy him Christmas gifts and I am fair in that way. However, he also does have a whole “extra” family that my nieces don’t have. So, I do get frustrated when I ask can I take the girls (there are two now) to Disney on Ice or a county fair and her husband will say only if his son can go too. I get blending is tricky sometimes but I also remind my sister the girls don’t get to go to the fair or zoo (for example) when he’s with his mom. It’s part of life… we all do our best but at the end of the day it’s sometimes hard to be fair. We might have a more natural connection to our own. I would say if the grandparents aren’t being malicious and it’s an occasional thing you should honor it. We don’t want to hurt any child’s feelings … they didn’t sign up to be part of a blended family but it’s okay to explain to them they get to do special things with their other parent or parents family side too.

I was in that sitiuation...starting at 10 years and on. The step-grandparents weren't "my grandparents" and I was well aware of that fact. They treated me kindly when I was there for holidays or whatnot, but I had my own grandparents. I didn't expect them to treat me the same as their grandchildren. An adult being ugly to a child is one thing, but to simply want to spend time with their own grandchildren,
and not other children? I think that is fine and the mother is being ridiculous. YABU

YOU choose who you marry and have children with, and accept the children they bring into the relationship. Other children shouldn't be forced onto everyone else because of the (let's face it, because if once married/divorced its likely to happen again, so probably temporary marriage) decisions you make. The children will just as quickly disappear out of their lives when the parents divorce again. That affects the adults feelings as well. They are bonded with their own, not with every kid that comes into your relationships. Again, as long as they aren't ugly to the other kids when they are around them, there's nothing wrong with wanting time alone with their own grandchild.

Who cares how the in laws feel? I don't understand why so many people are siding with them. I think it is messed up for them to even ask that knowing how your older kids might feel. Kids will not understand their reasoning behind the request, they will understand rejection. Obviously you can't force the in laws to spend time with them so I would have them spend more time with their biological grandparents or take them somewhere better so they don't feel left out.

They also didn't decide to have biological grandkids.

I would have them spend more time with their biological grandparents but by your logic @Firefly528 the OP'S younger children would be hurt and not understand why their siblings were spending time without them at their (the older dsc's) paternal grandparents. Now that's clearly nonsense so why why is it such a problem the other way round?
You seem mystified by children's ability to understand their different relationships within a blended family. If handled sensitively and openly children get it! The OP says her older dc don't call them grandparents so the dc clearly understand better than some posters.