Niece originally arriving with a man, related (8)
I believe the answer is:
narrated
'related' is the definition.
(I've seen this before)
'niece originally arriving with a man' is the wordplay.
'originally' suggests taking the first letters.
'arriving' becomes 'arr' (abbreviation used in transport).
'with' means one lot of letters go next to another.
'man' becomes 'ted' (Ted is a man's name).
The initial letter of 'niece' is 'n'.
'n'+'arr'+'a'+'ted'='NARRATED'
(Other definitions for narrated that I've seen before include "Recounted, recited" , "Related" , "Provided commentary" , "told a tale" , "Told a story, gave an account of" .)