Doctor has the right relation (6)
I believe the answer is:
mother
'relation' is the definition.
(I know that mother subproperty of parent (unspecified))
'doctor has the right' is the wordplay.
'doctor' becomes 'mo' (medical officer).
'has' is a charade indicator (letters next to each other).
'right' becomes 'r' (common abbreviation).
'mo'+'the'+'r'='MOTHER'
(Other definitions for mother that I've seen before include "She gives birth" , "Mum" , "Be overprotective" , "She gave birth to her Tom" , "Dam" .)