Can you tell me if there is any answers to why a child, 1 week old, has a smaller left eye ball, pupil and eye slit than the right?

See ophthalmologist: it might be a condition that called "microphthalmos", which is developmental defect. The condition can occur in the absence of other eye defects. However, there are other etiologies for that condition and need to be checked by pediatric ophthalmogist.

Molding: Molding of the skull occurs during the birthing process to allow passage through the birth canal, and can cause asymmetry of the facial structures. Wait a few weeks for this to resolve, and see your pediatrician for evaluation of facial asymmetry remains dramatic. Most people have SOME degree of facial asymmetry and this is considered normal.