Present for 2 year old, but....

[Kite22]

Wonder if anyone has any inspiration for me.

My dear friend has an almost 2 year old. They live abroad but are coming over for a few weeks to visit family, and are hosting a get together to see their friends, but hanging it on the 'hook' of inviting everyone to their ds's birthday celebrations.
Obviously, if I were generally going to any birthday party, I would take a present for the birthday child.
They will of course be flying home not long after the party, and I presume won't have the luggage space for 30? 40? extra toys / books / clothes and so forth.
Due to costs / time off work, etc they won't be back again for a few years, so no mileage in getting something they can leave here for when they visit Grandma, as he will be so much older when that next happens.

Any thoughts on what I could take ?

In this instance I would ask them what they would like you to do.

Maybe a paperback book? What the ladybird heard or similar? Or something like a t shirt? Both not too big. Or maybe some cash for them to put towards something bigger when they are home?

Lesser and Pavey melamine cutlery and plates make great presents for toddlers and they’re small and light.
The Aquadoodle travel mat/bag was a lifesaver when flying with our toddlers. Might be appreciated for the journey home?!

Thanks folks

Voucher for a toy shop or book shop near there home. I've flown back from a trip home (other side of world) with a 3 year old and hundreds of Christmas presents (well, maybe 25). Either seemed to be enormous/heavy, then about 12 different colouring books 'to use on the plane'. Honestly all well meaning, but don't give anything that needs to be packed!

Or, if they're here a while longer, something consumable (bath bombs? something edible? Voucher for something to do near where they're staying, etc).

That was my thinking BritinAus
If it were just me they were coming to see, my thinking would be different from knowing they will be seeing a lot of people whilst they are here, and I would assume a lot will think the same with "just an X to entertain on the plane" or "one extra Y - is only small and am sure you could fit in" which obviously isn't just "fit in-able" if there are 30 or 40 'Y' s.

Gift cards or vouchers sound like great suggestions. Could be something in digital, like a Birthday themed baby picture slideshow or something that isn't going to take up lots of space, like a family photo calendar with their pictures. Lighter snacks that are easily transportable (like chocolates or dry fruits) are an option too.