To expect people to RSVP to a child’s party?

[Birthdaypartydilemma]

My son turns 4 this weekend and has been asking for a party. We agreed as a nice treat. Being born in the first lockdown we’ve not really had a chance for a big get together and he wanted one with his preschool friends.
We’ve hired a local village hall and a bouncy castle. Nothing too swish as his friends ages are between 3-6 excluding a few family kids.
we sent out invites before the Easter holiday and his preschool were amazing in giving them to the relevant kids. About half have replied. We don’t care either way and if only one had replied our DS would have a fantastic time either way but obviously I’ve got party food and a cake etc to sort and we have no idea if the ones that haven’t replied are planning on turning up! Let alone allergies!!
AIBU to think that it’s common courtesy to send a quick message or even at pick up/drop off to say yes or no?

YANBU to think people should have the common courtesy to do this.

Unfortunately you will discover that many people have no idea about RSVP and basic manners when it comes to kids parties.

I remember one little girl in DDs cohort whose parents never responded. Sometimes she showed up at parties, sometimes she didn't, but it never seemed to occur to her parents to let anyone know either way. It wasn't just us who noticed this. I remember having this conversation with other parents while hanging about at the sort of soft play parties where parents usually stay.

You might have imagined the parents didn't know what RSVP meant, except when she was about six they threw a party for the first time and, not only did the invitation say RSVP but it included a date by which they wanted you to RSVP!

I read a good tip once,to get people to let you know if they were going to be able to make it or not. On the rsvp, there's normally a date to confirm by, like, please rsvp by the 22nd of April, then if peiple haven't rsvp'd by that date, later in the day or the day after, you contact the people to say something along the lines of, 'sorry to see you can't make it to X's birthday party as we hadn't received your rsvp by the 22nd, it would have been lovely to see you there but understand you can't make it'. I actually did this for a party I was throwing and the amount of people that got in touch that day to say they would still like to come if there was still space available was unreal!!! But you are definitely not being unreasonable to think it's at least common courtesy to say either way if you can/can't make it. I do always include, if you can't make it could you please let me know, so they know they have that option rather than just not bothering to reply.

Of course it is common courtesy. I always put an RSVP by * date on invitations too. It makes people pull their socks up a bit!

Buckle in, you've got more years of this to come. You'll wonder if you sent the invites out too early, too late, if it's clashed with another party invite, maybe your contact info was wrong...but ultimately people are shite and like to keep their options open, they'll rock up on the day or rsvp a day before.

YANBU did you put a date to RSVP by on the invite?

I stupidly didn’t put a date to reply by. Clearly a rookie mistake. As he’s our eldest and the eldest of his generation of kids in our family I didn’t even think to! Clearly a lesson learnt!