Closely follow mother’s principles (5)
I believe the answer is:
dogma
'principles' is the definition.
(dogma can mean beliefs)
'closely follow mother's' is the wordplay.
'closely follow' becomes 'dog' (I've seen this in another clue).
'mother' becomes 'ma' (Ma is another word for mother or mum).
'dog'+'ma'='DOGMA'
(Other definitions for dogma that I've seen before include "Belief, precept" , "Incontrovertible set of principles" , "Opinion viewed as truth?" , "Doctrine accepted as true without proof" , "Settled opinion" .)