Shelter king and son from sly looks (5)
I believe the answer is:
leers
'sly looks' is the definition.
(I've seen this in another clue)
'shelter king and son' is the wordplay.
'shelter' becomes 'lee' (as in lee side, the side sheltered from wind).
'king' becomes 'r' (abbreviation for rex, king in Latin).
'and' means one lot of letters go next to another.
'son' becomes 's' (genealogical abbreviation for son).
'lee'+'r'+'s'='LEERS'
'from' is the link.
(Other definitions for leers that I've seen before include "Looks lasciviously" , "Ogles" , "Reels (anag.)" , "Lecherous looks" .)