A method and orthotic for treating, substantially preventing, or minimizing the possibility of, human infant occipital plagiocephaly and sudden infant death syndrome (SIDS), utilizes or provides a garment dimensioned to fit a human infant. The garment (such as a vest or jacket) has an open top portion, a substantially closed front, a substantially closed rear, a first receptacle on the front, and a second receptacle on the rear and functionally cooperating with the first receptacle. Third and fourth receptacles are preferably also provided, the first and second receptacles on the left side of the garment, and the third and fourth on the right side. The garment may be primarily of a stretchable mesh fabric. A cylindrical or prismatic bolster (e. g. of firm foam or rubber) is provided in each of the first and second receptacles. The garment is placed on a human infant; and then the infant is laid on her/his side on a surface so that the bolsters substantially preclude the infant from rolling from her/his side onto her/his face or back on the surface.