Comic writer’s unhappiness about Dutch Royal family (9)
I believe the answer is:
wodehouse
'comic writer's' is the definition.
(PG Wodehouse)
'unhappiness about dutch royal family' is the wordplay.
'unhappiness' becomes 'woe' (woe is a kind of unhappiness).
'about' means one lot of letters goes inside another.
'dutch' becomes 'd' (common abbreviation).
'royal family' becomes 'house' (I've seen this before).
'woe' enclosing 'd' is 'wode'.
'wode'+'house'='WODEHOUSE'
(Other definitions for wodehouse that I've seen before include "Bertie Wooster's creator" , "P G ........., creator of Bertie Wooster and Jeeves" , "P G ..... created Jeeves" , "P. G. --, writer" , "P.G. -, Jeeves author" .)