Terrible failures that could make celeb sad (8)
I believe the answer is:
debacles
'terrible failures' is the definition.
(a debacle is a disaster)
'could make celeb sad' is the wordplay.
'could make' indicates anagramming the letters.
'celeb'+'sad'='celebsad'
'celebsad' anagrammed gives 'DEBACLES'.
'that' is the link.
(Other definitions for debacles that I've seen before include "failures" , "collapses" , "Complete fiascos" .)