Follow mother’s principles (6)
I believe the answer is:
dogmas
'principles' is the definition.
(I've seen this before)
'follow mother's' is the wordplay.
'follow' becomes 'dog' (dog can mean to follow or torment).
'mother's' becomes 'ma's' (Ma is another word for mother or mum).
'dog'+'mas'='DOGMAS'
(Other definitions for dogmas that I've seen before include "Set of principles set down as incontrovertibly true" , "Doctrines to be accepted without question" , "Doctrines put forward by church" .)