Barking pet guards the family member (12)

I believe the answer is:

stepdaughter

'family member' is the definition.
(I know that stepdaughter is a type of family member)

'barking pet guards the' is the wordplay.
'barking' indicates an anagram (UK slang for mad).
'pet'+'guards'+'the'='petguardsthe'
'petguardsthe' anagrammed gives 'STEPDAUGHTER'.

(Another definition for stepdaughter that I've seen is " Acquired relative".)

I've seen this clue in The Times.

Want a hint initially instead of a full solution? Install my app