Encourage, cheer up (7)
I believe the answer is:
hearten
I believe this clue is a double definition.
'encourage' is the first definition.
(I know that hearten is a more specific form of encourage)
'cheer up' is the second definition.
(I've seen this before)
(Other definitions for hearten that I've seen before include "given cheer" , "Make (someone) more confident" , "Comfort" , "Buoy" , "Encourage or cheer in cardiac manner" .)