Dot’s son getting a quick kiss (5)
I believe the answer is:
speck
'dot's' is the definition.
(I've seen this in another clue)
'son getting a quick kiss' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'getting' is a charade indicator (letters next to each other).
'a quick kiss' becomes 'peck' (I've seen this in another clue).
's'+'peck'='SPECK'
(Other definitions for speck that I've seen before include "Small spot" , "Small particle" , "lot of fat in school?" , "Dot" , "Tiny spot" .)