My sons get old bouquet (7)
I believe the answer is:
corsage
'bouquet' is the definition.
(synonyms)
'my sons get old' is the wordplay.
'my' becomes 'cor' (both are expressions of surprise).
'sons' becomes 's'.
'get old' becomes 'age' (to age is to get older).
'cor'+'s'+'age'='CORSAGE'
(Other definitions for corsage that I've seen before include "Spray of flowers" , "Flowers pinned to dress" , "Sort of bouquet" , "Flower worn on bodice" , "Nosegay, posy" .)