My DS is 21 in Dec (so this year for the first time he's having a combined Birthday/Christmas because he wants an electric guitar +amp)
Small presents
My DS would rather have money
but :
I bought a "Santa Needs Your Help Bob " book and clipped 10x £10 notes in the pages with snazzy paperclips .
'brand' under wear ( Calvin Klein boxer trunks ) TKMaxx or Sports Direct
Molton Brown 100ml shower gel
Some whitening toothpaste + a bamboo brush
Face products ( he likes Bulldog or Carbon Therapy )
Chocolates (who doesn't like chocolate
) Hotel Chocolate little boxes
Socks (useful)
Guitar plectrum set in a wallet
(I do a Dec 1st Hamper for mine -both adults- they get PJs , bathrobe if needed , socks, underwear . Then Chocolate Advent ) Useful and I know they need them .
Your two DS can help chose something , it'll mean a load to your nephew to recieve something they've picked too.