Name of son, also Yankee (5)
I believe the answer is:
sandy
'name' is the definition.
'son also yankee' is the wordplay.
'son' becomes 's'.
'also' becomes 'and' (I've seen this before).
'yankee' becomes 'y' (phonetic alphabet: alpha, bravo, charlie etc.).
's'+'and'+'y'='SANDY'
'of' is the link.
(Other definitions for sandy that I've seen before include "Ginger" , "Reddish (hair); like a good beach" , "gritty" , "Yellowish-brown; name" , "Alexander (abbrev.)" .)