Become happier (5,2)
I believe the answer is:
cheer up
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">become happier</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for cheer up that I've seen before include "Become happier" , "Turn that frown upside down" , "Take encouragement from" , "Get happy, lose the blues" , "Don't be so glum!" .)