Dramatic success involving family tree's production (7)
I believe the answer is:
catkins
'dramatic success involving family tree's production' is the definition.
I can't judge whether this defines the answer.
'involving family tree's production' is the wordplay.
'involving' means one lot of letters goes inside another.
'family' becomes 'kin' (synonyms).
'tree's production' becomes 'cats' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'kin' placed inside 'cats' is 'CATKINS'.
Can you help me to learn more?
(Other definitions for catkins that I've seen before include "Hanging spikes on a willow tree" , "They hang on willows" , "Hanging flowering spikes, of willow perhaps" , "Hanging spikes on willow trees" .)