How about two or three of those waterproof capes that come in small packets, take up little room to pack but cover everything when it rains? They only cost £2 or £3 each and will tear after a while but could be really useful. Maybe those together with one of the suggestions above.
I am not a great traveller, but I know a lot of people who are. 3 things that always seem popular (and indeed I find useful on my camping holidays) are: A Buff headband (so useful!) A length of silk, about 2 metres x 140, which can be worm like a sarong, draped like a scarf or shawl. I have just bought a length of habutai silk and hemmed it (very easy) A pashmina which can be used as a warm shawl, or an extra covering. All of these fold into tiny spaces and weigh very little. Iput them all in a pocket of my rucksack.
My daughter is off on her travels in December and I want to buy her something sentimental to take with her . A couple of years back I bought her a lovely St Christopher on a necklace when she went off to Australia and she bought us both matching rings which neither of us ever take off . I know she will give me a really thoughtful loving present but I’m completely stumped as to what to buy . She wears minimal jewellery mainly only stuff that has meaning and as she’s travelling through Asia volunteering and having a good time I don’t want something too expensive that she will have to worry too much about . Any ideas please