Stress fractures overwhelming writer's family members (7)
I believe the answer is:
sisters
'family members' is the definition.
(sister is a type of family member)
'stress fractures overwhelming writer's' is the wordplay.
'fractures' is an anagram indicator (I've seen 'fractured' mean this).
'overwhelming' is an insertion indicator.
'writer' becomes 'I' (the person who is writing these clues).
'stress' with letters rearranged gives 'ssters'.
'ssters' enclosing 'i' is 'SISTERS'.
(Other definitions for sisters that I've seen before include "Nuns - nurses - siblings" , "Family relatives" , "Female siblings" , "Resists for relatives" , "Aunts may be" .)