Information involving son and daughter makes one cheer (7)
I believe the answer is:
gladden
'one cheer' is the definition.
(I've seen this in another clue)
'information involving son and daughter' is the wordplay.
'information' becomes 'gen' (gen can informally mean information).
'involving' is an insertion indicator.
'son' becomes 'lad' (lad can mean a boy or son).
'and' says to put letters next to each other.
'daughter' becomes 'd' (genealogical abbreviation).
'lad'+'d'='ladd'
'gen' enclosing 'ladd' is 'GLADDEN'.
'makes' is the link.
(Other definitions for gladden that I've seen before include "raise spirits" , "Hearten" , "Lift (the heart)" , "Make pleased or happy" , "Give pleasure to" .)