According to The Discovery of Witchcraft of 1584, May Eve ( Walpurgis Night) is the
time you must guard your children against witches.
" The Devil teacheth witches to make ointments of the bowels and members of
children, whereby they ride in the air and accomplish all their desires.
So if there be any children unbaptized or not guarded with the sign of the cross
or orisons (prayer) then the witches may and do catch them from their mother's side
at night, or out of their cradles...and after burial steal them out of graves and
seethe them in a cauldron until their flesh be made potable."
To ensure this doesn't happen place a crust of salted bread under
the baby's pillow, also hang garlic and rowan around the cradle.