My mum still sometimes buys clothes for me, and usually it's really cute things like blouses with ribbons on them and last week I came home from school and she presented me with penguin pyjamas! I'm kind of obsessed with penguins and the pyjama top has a big penguin on the front with blushy cheeks and a scarf and it's just so adorable.
I guess girls have it easier to find cute clothes, especially with the fashion (at least in Germany) turning more towards girly clothes again. I have lots of cute outfits with animal prints or little bows and no one bats an eye if I wear them in public. Heck, even my winter coat is in a "little girl" style.
But I agree with there being no cute bed sheets, at least in the stores. I actually think my mum has kept some of our bedding from when we were children, with teddy bears on them, and as far as I remember, they're adult sized. I don't knwo where one could buy them nowadays though...