Resist being corrupted by family member (6)
I believe the answer is:
sister
'family member' is the definition.
(I've seen this before)
'resist being corrupted' is the wordplay.
'being corrupted' indicates an anagram.
'resist' anagrammed gives 'SISTER'.
'by' acts as a link.
(Other definitions for sister that I've seen before include "Nurse, nun and sibling" , "twin?" , "Member of family" , "of the same origin" , "woman in hospital" .)