Bad forefathers I worked out to be group of similar type (5,2,1,7)
I believe the answer is:
birds of a feather
'be group of similar type' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.
'bad forefathers i worked out' is the wordplay.
'worked out' indicates anagramming the letters.
'bad'+'forefathers'+'i'='badforefathersi'
'badforefathersi' with letters rearranged gives 'BIRDS OF A FEATHER'.
'to' is the link.
Can you help me to learn more?
(Other definitions for birds of a feather that I've seen before include "they combine well!" , "like-minded people" , "Likes" , "sitcom" , "Like people" .)