Why are some people crosseyed and how do they see properly? Can it be fixed and how is it caused?

When I was a baby, my eyes would cross all the time. the doctor said that I had "lazy eye". My eyes are much improved now, thanks to God, but when I haven't had planty of sleep and my eyes get tired, my left one will cross over a little bit and make it hard for me to focus on anything up close.
You might not want this answer, I don't know, but prayer is the only thing that healed my eyes. I did not wear my glasses like I was supposed to and the doctor said my eyes would never get any better. My right eye is now 20/20 and my left, 20/40, which is a grand improvement from what they were. At one point I know one of my eyes was in the 80's!
Hope this helped.

The correct term for the condition cross-eyed people suffer is Strabismus.

This is from the Wiki article on it:

"Strabismus can be an indication that a cranial nerve has a lesion. Particularly Cranial Nerve III (Occulomotor), Cranial Nerve IV (Trochlear) or Cranial Nerve VI (Abducens). A strabismus caused by a lesion in either of these nerves results in the lack of innervation to eye muscles and results in a change of eye position. A strabismus may be a sign of increased intracranial pressure, as CN III is particularly vulnerable to damage from brain swelling."


Treatment:

As with other binocular vision disorders, the primary therapeutic goal for those with strabismus is comfortable, single, clear, normal binocular vision at all distances and directions of gaze.

Whereas amblyopia, if minor and detected early, can often be corrected with use of an eyepatch on the dominant eye and/or vision therapy, the use of eyepatches is unlikely to change the angle of strabismus. Advanced strabismus is usually treated with a combination of eyeglasses or prisms, vision therapy, and surgery, depending on the underlying reason for the misalignment. Surgery attempts to align the eyes by shortening, lengthening, or changing the position of one or more of the extraocular eye muscles and is frequently the only way to achieve cosmetic improvement. Glasses affect the position by changing the person's reaction to focusing. Prisms change the way light, and therefore images, strike the eye, simulating a change in the eye position.

http://en.wikipedia.org/wiki/Strabismus