It’s about mothers concealing their aspirations (6)
I believe the answer is:
dreams
'aspirations' is the definition.
('dream' can be a synonym of 'aspiration')
'it's about mothers concealing their' is the wordplay.
I cannot really understand how this works, but
'about' could be 'rea' (I've seen this in other clues) and 'rea' is found within the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for dreams that I've seen before include "Fantasy ambitions" , "Imaginings" , "Reveries or cherished aspirations" , "Thoughts and visions during sleep" , "Fantasies; fantasises" .)