Baby Tears

Dear Kurt,

In fact, most babies will start to produce tears at about 3-4 weeks,
although around 12-15% are able to do so within 5 days of birth.
However, the internal surfaces of the eyelids are lined by a special type 
of skin, called the conjunctiva, which contains many small mucus secreting
glands. Also, around the free edges of the lids are modified sebaceous and
sweat glands, and the secretions of these, together with the fact that a 
baby spends most of its time asleep (and thus with its eyes closed), are
sufficient to provide enough moisture in the early days.

Similarly, the mouth is lined with a special type of skin called mucosa,
containing many mucus-secreting cells, which serve to maintain a moist 
environment. Since one of the main functions of saliva is lubrication of
solid food to allow swallowing to take place, then any initial paucity of
production will clearly not have a detrimental effect.