Collocations for sister - noun

big, elder, older
baby, kid (informal), little, younger
twin
full (= sharing both parents)
adopted, adoptive
beloved, darling, dear
annoying, bratty (informal, esp. AmE)
my bratty little sister

dead, deceased, late
long-lost
a refugee who traced his long-lost sister

unmarried
sorority (AmE)
Carolyn's sorority sisters at Indiana University

brothers and sisters, brothers or sisters
Brothers and sisters do not always get on.
I have no brothers or sisters.

like sisters
The two girls are so close, they're like sisters.