Shorts for slim 12 year old

[sahbear]

Help!
I can't find any shorts to fit DS1 that he will happily wear, and he is off camping for a week soon.
We have spent an hour in Primark trying clothes on, and wandered around lots of other stores.
He is slim and not particularly tall. They are all either huge on the waist and with the exception of swim shorts don't have proper drawstrings or if we go a size smaller too short.
He doesn't want chinos, jeans, fleece or ones that look like swimming shorts.
So anyone know where I can get cotton shorts or similar with a small waist?

next have some drawstring ones here if that helps at all x

Thanks, but they fit into the 'fleece' category. DS wears these as pyjamas so won't wear them in the day...
Something like this but lighter material would be perfect, as long as the drawstrings pull tight enough.

I think this is what we want
tuclothing.sainsburys.co.uk/p/Red-%26-Black-Twill-Shorts-2-Pack-%283-14-Years%29/134774714-MultiColoured?searchTerm=:newArrivals&searchProduct=
But out of stock in all suitable sizes. A lot of drawstrings just seem to be for show and don't actually do anything.

How about outdoor style ones like these:

www.trespass.com/marty-boys-cargo-shorts

The brand comes up small and the trousers are quite hardwearing, DD has several of their hiking trousers for Scout camps.

H&M have some in cotton jersey fabric (not fleecy, more like t-shirts) with drawstrings. Gap also had some plain cotton ones (not chinos) which were quite small in the waist, they had a gathered elastic waist rather than the adjustable buttonhole elastic but they came up small enough to for my slim DS11

Thank you both. I have found some at Sainsburys with a drawstring waist, but will have a look at Trespass and Gap too.

I agree try the outside brand ones: trespass, mountain warehouse, decathlon. Often have button adjustable waists. Look at the zip off long trousers also.

Was going to say Gap too. My ASD DS is VERY particular and Gap usually have something.

You could try French brands which tend to be narrower and more French kids' clothes have adjustable waists as well.