Unexpectedly having run short of little boy's clothes? (3,2,3,4)
I believe the answer is:
out of the blue
'unexpectedly' is the definition.
(synonyms)
'run short of little boy's clothes?' is the wordplay.
I cannot quite understand how this works, but
'of' could be 'o' and 'o' is found within the answer.
'little' could be 'l' (abbreviation) and 'l' is present in the answer.
'boy' could be 'b' (abbreviation used in schools) and 'b' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
'having' acts as a link.
Can you help me to learn more?
(Other definitions for out of the blue that I've seen before include "From nowhere" , "Suddenly" , "Without warning" , "Entirely unexpectedly" , "Quite unexpectedly" .)