It may be what is called cherry eye, my chihuahua got that when he was just a little puppy. What it is is a third eyelid (which all dogs have) but it protrudes from the inner corner of the eye. I thought about getting my boy surgery, but also learned that can really dry out their eyes and cause later eye problems. He is five now and his "cherry eye" has gone back in for about four months straight now.seems to have cured itself.
