Relative is most confused when not having a rest (5)
I believe the answer is:
uncle
'relative' is the definition.
(I know that uncle is a type of kinsman)
'most confused when not having a rest' is the wordplay.
'most confused' becomes 'unc' (I can't justify this - if you can you should believe this answer much more).
'when not having' is a deletion indicator.
'a' becomes 'an'.
'rest' becomes 'lean' (I've seen this before).
'lean' with 'an' taken away is 'le'.
'unc'+'le'='UNCLE'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for uncle that I've seen before include "Dad's brother" , "Law enforcement body" , "Family relation" , "He's related" , "older relative" .)