Cincy had issues with her third eyelid when she was just a pup. When she was 2 1/2 mos old the thrid eyelid of her left eye prolapsed (Cherry eye). The vet was able to surgically reattach it with no further issues. When she was 3 1/2 mos. Cincy developed warts in her mouth partially from a weakened immune system from having undergone anestesia at such a young age. At that time her right eyelid prolapsed and it too had warts on it, so it couldn't not be reattached and was removed. So far so good (she will be 1 yr in two weeks) We will have to watch her for the rest of her life to be sure she doesn't not develop dry eye, because the tear gland was removed, but so far she has done fine.

Good luck whatever you decide