Good morning,
The third eyelid appears at times of injury, illness, infection or stress.
http://www.seefido.com/html/where_is_the_third_eyelid_of_t.htm#
Even worms or a GI upset can cause this.
If she has diarrhea your baby can have Immodium or kayopectate:
http://www.peteducation.com/article.cfm?c=0+1459&aid=1432
Rinse the eye with plain saline made for contact lens wearers.
Try a small amount of boiled chicken with all fat drained off, chop meat , or baby food with no onion, beef, turkey, etc
Add unflavored pedialyte to her water 50/50 to hydrate her and balance her electrolytes.
Put a drop of pancake syrup on her tongue to raise her blood sugar in case she is a bit hypoglycemic. That should perk her up.
Also give her one teaspoon a day of plain yogurt to keep "good" bacteria in her system.
If she develops any abdominal oor eye pain, bloating, constipation or cannot keep anything down she needs to be seen by a vet.
Please let me know how she is doing. I will always be here for you
I hope your baby feels better very soon..
Best wishes for her,
Terri
Healthcare Expert
Expert in canine health and behavior. 20 years of experience with dogs