Old king hugs wayward son for comfort (7)
I believe the answer is:
console
'comfort' is the definition.
('console' can be a synonym of 'comfort')
'old king hugs wayward son' is the wordplay.
'old king' becomes 'cole'.
'hugs' means one lot of letters goes inside another.
'wayward' indicates an anagram.
'son' with letters rearranged gives 'ons'.
'cole' going around 'ons' is 'CONSOLE'.
'for' is the link.
(Other definitions for console that I've seen before include "give reassurance" , "Key-desk of an organ" , "Comfort - cabinet" , "Give moral or emotional strength to" , "Comfort - control panel" .)