Activity for writer's daughter: a water sport (8)
I believe the answer is:
drafting
'activity' is the definition.
(drafting is a kind of activity)
'daughter a water sport' is the wordplay.
'daughter' becomes 'd' (genealogical abbreviation).
'a water sport' becomes 'rafting' (I've seen this before).
'd'+'rafting'='DRAFTING'
'for writer's' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for drafting that I've seen before include "Drawing up an outline" , "Making rough preliminary written version" , "Writing a preliminary version" , "Impressing" .)