Frog eyes have eyelids , both an upper and a lower one.
It might be a kidney problem. See a doctor. It is serious even if it is not a kidney problem.
M83- Lower Your Eyelids to Die in the Sun
Swelling of lower extremities is called in very old books "dropsy", and is called in modern medicine "edema", or simply "retaining water". It can have a large number of causes, but one of the most common, especially in the elderly, is coronary insufficiency - your heart is not working as hard as it should. But I stress what I said above: It can have a number of different causes. If you have developed it, see your doctor.
6 - two upper, two lower and two third eye lids. The third eyelid is under the lower lid and serves like a windshield wiper to clear the cornea when the camel blinks. Camels actually have three eyelids! Two of them have lashes, and the third is thin. Camels have three eyelids per eye so they have six eyelids total. The extra eyelids help protect it from sandstorms. The third eyelid is translucent (they can see through it) so their eyes will be covered during sandstorms.
The medial angle of the eye is the angle formed by the upper and lower eyelids at the medial canthus. It is sometimes used to describe the medial canthus itself. You might think of it as the spot where your eyelids meet closest to your nose.
Three. They have the upper and lower lids, similar to humans. They also have a third membrane that acts as an eyelid, so to speak. The third "eyelid" moves from the outside edge to the inside edge.
He probably should see his doctor again immediatly if the swelling continues...