Miriam,

This could be some medical problem but my first instinct would be food
intolerance or allergies.  Instead of cutting out various foods one by
one, I would suggest rather that the mom go on a 'cave man' diet 'ala Dr.
William Crook which is:

Meats (any BUT Beef, chicken or pork)

Grain alternatives (amaranth, quinoa)

Fruits (any but apples and citrus fruits

Nuts (filberts, Brazil nut, English walnut, almond or pecan)

Vegetables (any BUT corn, white potato, tomato and legumes

Safflower, Sunflower, Walnut, Olive or CAnola oils

Beverages (Mineral water, spring water)

This diet avoids every food you eat more than once or twice a week.
She should stay on diet 5-7 days, and can then start adding back 1 food
at a time in small amounts.  She should keep track of baby's behavior by
charting during this time.  Remember that it can take 3 weeks to
eliminate Dairy protein from Mama's system and therefore baby's.

More information can be gotten from "Detecting Your Hidden Allergies by
William G. Crook, MD"

It's certainly worth a try.  I've found Mom's are usually surprized to
find symptoms of their own clearing up on an elimination diet, and it can
make a dramatic difference in baby.  If baby's behavior does not change
then she can sure feel free to search for other possible causes.  It
seems to take several days to see changes.

Good Luck.

Katherine Catone, LLLL, IBCLC