Niece is turning 30 and we'd like to get her a small (£25ish) gift, typically for the decade years we do buy gifts for adult relatives. She has ASD, quite limited interests (even her favourite animal is one that doesn't really pop up on clothes or jewellery etc 
) and hobbies. Baking and cooking the big two but pretty much has everything she needs. She lives in a small flat so don't really want to give her 'clutter'. Very into space but has binoculars for stargazing, books, a galaxy lamp, posters/prints, bedding already. Similar with the few tv shows she's really into, she has the dvds, related books, funko figures.
The only idea we've really come up with is a cactus to add to her collection...or socks, she loves socks. Cactus socks???