Excited seeing the daughter crossing brook (8)
I believe the answer is:
thrilled
'excited' is the definition.
(thrilling is a kind of exciting)
'the daughter crossing brook' is the wordplay.
'daughter' becomes 'd'.
'crossing' means one lot of letters goes inside another.
'brook' becomes 'rill' (I've seen this before).
'the'+'d'='thed'
'thed' enclosing 'rill' is 'THRILLED'.
'seeing' is the link.
(Other definitions for thrilled that I've seen before include "Feeling intense pleasurable excitement" , "Delighted" , "Exhilarated" , "Excited and pleased" .)