Problem child (5)
I believe the answer is:
issue
I believe this clue is a double definition.
'problem' is the first definition.
(I've seen this before)
'child' is the second definition.
(I've seen this before)
(Other definitions for issue that I've seen before include "Topic (to be addressed)" , "Problem - child" , "Problem < children" , "Give or send out" , "Question in dispute to be settled" .)