Kid's sizes/clothes?

[Bardotdot]

Sorry I know this is a bit of a 'piece of string question' but would appreciate some guidance? Buying a personalised hoodie for 9 year old nephew. Really need to order today. Can't get hold of his mum.
He is not tiny but he is one of the smaller boys in the class. He is not thin or fat.

The 7-8 year old hoodie says 30 inches
The 9-11 year old says 32 inches.

I don't know what to do. The 9-11 surely is big enough for 11 year old but if he's a bit small for 9 is that likely to be too big?

As said in personalised so can't just swop it.

Hoodies are better a little bigger so I would go for the bigger size. Better to be a little bigger than too small.

Go for the bigger size. If nothing else he'll hopefully get more wear out of the larger one.

You're fab thank you so much!