Some infants have a preference for cluster feeding. This is a series of nursing contacts interrupted by only brief pauses for dozing in the comfort of mother's arms. These cluster feeds may then be followed by a longer span of sleep for the infant. Or an infant may experience frequency days. This series of two or three days of marathon nursing has the miraculous effect of stepping up a mother's milk supply to correspond with the infant's nutritional needs in a hurry. An understanding of an infant's breast-feeding patterns can reassure a mother that her breast milk alone can satisfy her baby's need for comfort and nutrition.