if you raise crows they will take your eyeballs from your face afterwards when they can do things by themselves.
this saying means: if you are feeding a 'monster' he will end up eating you. (people usually put their interests over others' interests)
The saying in English is: breeding crows peck your eyes and you (from google)
In Spanish: Cría cuervos y te sacarán los ojos (not that far of English version)