Social workers' brief ultimately failed to protect child (8)
I believe the answer is:
termites
'social workers' brief ultimately failed to protect' is the definition.
I can't judge whether this definition defines the answer.
'child' is the wordplay.
I cannot really see how this works, but
'child' could be 'mite' (I've seen this in other clues) and 'mite' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for termites that I've seen before include "Destructive workers" , "Flightless insects living in mounds" , "Ant-like social insect that feeds on wood" , "Ant-like insects that feed on wood" .)