Can young child attend classmates party when a little poorly?

I would message the mum and ask first.

I’d personally ask the parent(s) hosting the party x

No, I would be afraid of judgement . Plus the beginning of a cold is still a cold and therefore contagious. My son has asthma and any viral respiratory illness can quickly become a week long ordeal. So I'd be pissed personally.

We missed out on a party last weekend and another party late last year due to this. My daughter just explained to her friend why we didn’t go because we didn’t want to get her sick and she understood. I think I was more upset we couldn’t go 🤣

You may get judged for cancelling last minute, just like you may get judged for showing up. If your child doesn't have a fever or need paracetamol, just go or call to ask and see how they feel about it.

No I wouldn’t- honestly asking the parent hosting is just putting them in such an awkward position. Chances are they will say yes when deep down they would really rather u kept ur poorly child at home. And then poor little guy is playing around coughing all over the birthday cake and you’re on edge thinking ur being judged and u should have just left little Joey at home! It’s not worth it… trust me I’ve been there. 😅