Argued violently after son gets sweet (7)
I believe the answer is:
sugared
'sweet' is the definition.
('sugared' can be a synonym of 'sweet')
'argued violently after son' is the wordplay.
'violently' is an anagram indicator.
'after' means one lot of letters go next to another.
'son' becomes 's'.
'argued' anagrammed gives 'ugared'.
'ugared' after 's' is 'SUGARED'.
'gets' is the link.
(Other definitions for sugared that I've seen before include "Sweetly coated (almond)" , "Sweetened" .)