Hi,
Most nipple discharges are caused by benign conditions and is rarely a sign of breast cancer. Fibrocystic breast changes can, at times cause secretion of clear, white, yellow, or green nipple secretion.
It is meaningless unless your mother notices that the discharge is spontaneous, (comes out without squeezing) is persistent, particularly if it’s bloody and is associated with a lump, nipple or skin changes. If this happens it becomes concerning and she should see her doctor to have this problem evaluated and treated.
Discharge from the nipples, when they are squeezed, increases the Prolactin hormone level in the body and often women who are concerned about breast secretions may actually cause it to worsen by repeatedly squeezing their nipples to check for nipple discharge. In these instances, leaving the nipples alone for a while may help the condition to improve.
Best wishes to you both ..