My DD has a Kanken bag in khaki, she's hankering after the dark red one now.
My DS will be 18 in Dec , so Milestone Birthday and Christmas , and he's impossible to buy for too 
My D will be 15.6 , she writes A List 
I do Hampers on 1st Dec now (started last year, they thought it was better)
So PJs , new robe, bath smellie, sweets
I'm doing an Advent for DD with a Beauty Gift in a clear bag (mini travel sizes of shampoo, face pack, soap , candle ,sort of thing) rather than buy one and she doesn't use them (I've had a look through the previews of Beauty Advents)
DS would probably like a couple of £1 coins each day.
They'll have a Chocolate Advent (of course)
We save £2 coins + 10p/5p/10p/2p/1p in a tin and I cash them up and divide by 4 of us. They can buy what they want (its usually £60-£80 each)
I have no clue what DD want clothes wise so she'll get a Gift Card for TopShop and Pink to choose herself . Last year she chose a really nice grey top and leggings from Pink .
DS will probably get money (he saves everything)
He's already got a big TV as an early present + a stand.
He might buy himself the new XBox so we'd get him games.
Some 'named' (like Calvin K or similar) underwear though DD said he won't care if they're CK or M&S !