Have a pet baby owl worth being trained (5,1,6)
I believe the answer is:
throw a wobbly
'have a pet baby owl worth being trained' is the definition.
I can't tell whether this defines the answer.
'baby owl worth being trained' is the wordplay.
'being trained' indicates anagramming the letters (to train can mean to grow something into a shape).
'baby'+'owl'+'worth'='babyowlworth'
'babyowlworth' with letters rearranged gives 'THROW A WOBBLY'.
Can you help me to learn more?
(Other definitions for throw a wobbly that I've seen before include "Go ballistic" , "Have a tantrum (colloq.)" , "Have a (jelly-like?) tantrum" , "Become very angry" , "Have a fit" .)