All 4 of us to attend bday party?

Unless they have specifically said all welcome then don't do this.
Kids parties are not nice family outings!
One adult attends and the other adult looks after the sibling elsewhere (unless it's a party at a public venue, in which case bringing a sibling can be acceptable as long as you pay for them and don't expect them to be part of the party group e.g. expecting food, party bag, being able to play with the sibling and their friends).

Good lord why would you do this?? What happens if everyone does this? If you invited 2 people to your house ( child and parent) and then double that number turned up would that be ok?? And then multiply that by the 8 kids you invited??

a nice family thing to do on a weekend

No.

It's a child's birthday party, the invitation is for your child, not 4 people.

One parent only - think of space and also extra work involved (albeit making an extra drink, but if all families take two parents, that could be ten extra drinks).

I'd say one of you goes, and maybe the other could come and collect five mins before end of party - that way they get to say 'hello' to one or two others.

We’ve done both, and when we’ve had parties it’s been a 50/50 split if all or just solo sibling/parent show. If it’s a no siblings thing I think that should be made clear cause this expectation (either way) so often ends up being an issue! If I were you I’d just ask them if there’s a number on the invite. Something like “thanks for the invite! X would love to come. Is it a family affair where all of us would be welcome (X’s parents and newborn too) or is it best to have just X and one parent so as to not overwhelm bday girl/boy and have the house overrun with guests? No prob either way. Thanks X is looking forward to it!”

A family is DDs school used to do this. Both parents would turn up at class parties and do every school drop off and pick up together. Was very weird. They’d drive to the school and stop outside the gate on the yellow lines in their convertible even though they lived a 10 minute walk away. They’re really lovely people too but this annoyed me.

My question is, would it be unreasonable for all 4 of us to rock up? Is that weird?

@wanderingwillows Yes and yes, especially as it is at someone's house. If all the families turned up it would be too crowded and too overwhelming for the little ones. At that age one parent would stay, but having other parents and siblings invite themselves in would be very rude.

I found socialising with other parents at parties very helpful, and I hope you manage to find some like minded parents. Unlike many mumsnetters I enjoyed socialising with the other parents at children's parties.

Ask. We have garden parties for DSs birthdays, we have a big garden and DH loves hosting and socialising so everyone's invited.
But they may have a small house and can't accommodate that many people.

It’s fine both parents attending a big class party say at a village hall or large soft play venue, but might be a bit much in someone’s home that youve never met. Obviously at that age one parent needs to stay. x

Where I live it’s expected that the whole family goes and nursery parties have been more about parents getting to know each other. Then again most parties are held in parks or rented spaces probably for this reason.

I think it's fine, not weird at all. We never hosted a party at home but did go to a couple and we were far from the only ones who went together.

At all of my children's birthday parties when they were nursery age and under, it was really common for both parents to come along, including when we had a party at the house. I actually thought it was totally normal until reading this thread.

No don’t do this. If they’ve invited 10 kids, imagine if every family did this? It would be absolute bedlam and unless they live in a mansion the house/ garden would be completely bursting. And it adds additional stress to the person running the party who’s just trying to give their DC a treat.

Remember- this is about the birthday child and not you/ your family.

And I am not germ-phobic at all but a toddler birthday is literally a Petri dish of bodily fluids. I’m not sure I’d take a newborn unless it was genuinely unavoidable.

Do not all go.
You go with your child and leave dh with baby or vice versa.

If i knew the mum (you dont) I'd ask but in these circs I'd either send 1 parent with the invited child or not go if family time is more important than the party.

Edit: I think if its a church hall or something I might chance it but in someone's house def not...

Im in London and like honeyhonay and it is really common for both parents (and a newborn) to go. But it is location dependent. Sometimes invites say e.g. only 1 parent, if space limited.

This depends on the venue and the age of the sibling for me. If it’s at someone’s home then no just one parent as if every child invited brought both parents and siblings it could get very cramped quickly. At village hall / indoor play with ample space and seating it’s absolutely fine.

Bringing a newborn to a soft play party is fine but once they’re older don’t bring them to anything where they’re going to increase the cost of the party for the host. We’ve had people bring siblings to our parties and then been charged an extra £12.99 per head for each one. Or similarly don’t bring them to anything where they’re going to stop their older sibling having fun with their friends.

Your experience is not universal though, if OP isn’t sure then it’s better to be cautious since she clearly doesn’t know the parents well enough, but for many people parties of preschoolers is an family thing.

Where I live, it's pretty common for the whole family to go as it's quite a friendly community but sounds like that's not the norm! I think I'd send DH and stay home with baby.

On the other side of things I wouldn’t mind if you all turned up, I think it would be nice to meet other parents.

When we hosted 4 and 5yr old summer birthday parties we often had the whole family come. It was relaxed and enjoyable.

If you were worried you could ask the host. Personally I wouldn’t mind at all.

No. Of course not. Not sure if your daughter is 2, or you mean your second daughter, it's ambiguous but an invite is for the child only. If one person feels they need to stay then ask, but it's not a family outing.n

Nope - divide and conquer. A stranger’s toddler birthday is not a ‘nice family thing to do’. It’s something to be endured and then you can go and do a nice family thing after.

Mumsnet generally say it’s weird so I imagine it’s area dependent.
Nursery parties in London, in my experience, have always been predominantly 2 parents going and socialising with the other parents along side the kids playing at the party. But most parents in the nursery knew eachother and there was very much the culture of socialising with other parents outside drop off.
If you aren’t sure and particularly as it’s in someone’s home then one of you stays with the baby and one attends the party.

If it’s at someone’s house, I’d say one parent only. When it’s been at a leisure centre etc it’s been a mixed bag but still mostly only one parent. Especially if you have a second child, they’re usually allowed to come along if you have no option but people would expect you to leave them at home if both parents are available.

Why on earth would you think the invite is a " nice family thing" for all four of you???????