They need a:

Portable mini fridge!

Be a cool relative / friend / total hero with this gift! I bought the pink one and the blue one for each of my teenaged nieces. They like to keep their makeup in it (who knew?! It’s a thing!), plus a couple cans of pop and a snack. Then they don’t have to leave their room to see their parents (ugh, thank god! Total lifesaver)! I’ve also heard it can be unplugged and keep hot food warm for an hour or so. Very versatile. Comes in many colours, even a black dry-erase version!