For saying no?

My oldest DC was 2y 10 months when our second child was born.

honestly, they had quite a few days away with Granny and Grandpa in the first year, which wasn’t usual before their sibling was born. DC bloody loved having some time being the centre of attention and being made a fuss of by grandparents.

maybe now isn’t the right time but I wouldn’t discount it at all, your DC might actually appreciate the break

There's always going to be things that one child gets to do without the other.
If the youngest is feeling a little insecure it would be a great opportunity to make her feel special by having some one on one time with granny gives you a bit of a breather and builds the youngest confidence back up.
Really can't see the problem she could go for the day but not sleep build up to that

If she’s nearly 3 could you ask your eldest DD? It could go either way - she might take it as being separated from you or she might see it as a special treat just for her. I’d ask her and see what she thinks?

Sadly your child sees it as a punishment, which we know isn't, so you're doing the right thing. Jealousy will eventually stop but for know you're doing what's right
You've got this

It doesn't matter what anyone else would have done/has done/thinks you should have done. You are the parents here, and you made a decision. Your mother should respect that decision, even if she doesn't like it.

Not unreasonable at all.

I have a 4 yo and 1 yo so DD was 3 when son was born, she’s always loved school but started crying every morning at one point. Took a couple of weeks but I realised that she’d figured it was just me and baby at home together, so I started telling a little white lie that baby was going to childminder and I was back at work…straight away she started being excited for school again.

We do what’s best to protect their little hearts - new sibling is already a lot for them

I think that grandparents who truly want to help, don't get sulky - they support the mother.

The OP's instincts are absolutely spot on - her child needs her and OP wants to be with her toddler. She doesn't have to justify it or force herself to do something she's not comfortable with, just because someone else wants it!

Personally, my kids would have loved to have had a one on one break with grandparents for a day.
The problem is not that the toddler is missing you but more that they are missing one on one attention from you.

Your older child might like a break from the baby too.
It seems like the toddler is not 100% happy each day with you and the baby so what's to lose? They might come back cranky but they could be just as cranky staying home.

I’d have let them go. Let them have a bit of 1:2:1 time with their grandparents and be spoilt.

I would have said yes and made it sound special or exciting, she’ll get loads of one on one attention from grandparents which it sounds like she could do with.
You’re not a dickhead for saying no it’s up to you what you decide for your children

Omg. Your mom is being an absolute ass!

of course you’re not letting a 2.5 yo sleep over and cause trauma. And what? If the littlest wasn’t on the boob then they would be kidnapped too???!

ugh. Sounds like a MIL thing, not a mom thing.

Not getting lots of time off is a great reason to let Granny do Lapland - it’s only a day trip anyway. Use the scarce holiday for something like Disney. Why would you want to deprive your child of something nice just because you’re not there?

Maybe op doesn't want her children whisked away from her on holiday? It's not unreasonable. We don't get masses of time off and I wouldn't want DS going away without us.

for example she said she’s saving to take both kids to Lapland when they’re old enough. Me and DH expressed gratitude but just explained nicely we would like to do a big trip like that with them , we’d want to take them etc

You could always take them somewhere else. They can have more than one big adventure.

I completely get this. My eldest is 2years 6 months and baby 6 months. It’s two boys. It took a long time for the eldest to accept the baby. We saw grandparents semi frequently and he’s want to leave the baby with them so he could have 1-1 time with us. He now likes his baby brother but we do still have adjustment issues. I’m on maternity leave but we still send the eldest to nursery, he absolutely hates leaving the house, wants to stay with me etc (he has a great time there and come homes telling me all about it) but he struggles with ‘being sent away when mummy is still at home giving the baby all the attention’ you’re not being unreasonable refusing to send your eldest to grandparents, but maybe ask her what she wants to do.

Why doesn’t your mother understand? I am baffled.

If op said no that's fine, I don't see the big deal. She's the parent and decides. The toddler isn't going to be scarred for life. I'm sure toddler will see plenty of gps in the future!

Could your Mum just take your eldest out for a couple of hours instead as a special treat? If you are not comfortable with them going overnight?

I think you’ve looked at this wrong I don’t think your child would see this as being left out I think they’d find this exciting getting grandparents to themselves and how fun it would be. If your on edge you could always be on standby if she did have a wobble but I dnt think that would happen. I’d be grateful for the help and see it as you can actually have the time with your baby without feeling guilty of how much time you are spending with them :)

You should ask DD what she would like to do, it might be nice for her to go somewhere and be the centre of attention without having to share with a baby.