The present invention is a simple, adaptable orthotic device that can correct and/or prevent deformational posterior plagiocephaly, especially if used before the infant is 4 months of age. The manufactured article provides an anatomically correcting, adjustable, concave-shaped resting surface for an infants head in a manner that effectively eliminates uneven pressure on the infants occiput. The orthotic device has a modular design which permits easy adjustments of the devices head cavity to accommodate differences in individual infant head size and shape, thereby providing the infants head with a custom fit. Also, as the infant continues to grow in size, the adjustable head cavity and torso recess features of the orthotic device allow the contoured spatial volume and dimensions of the molded supporting surfaces to expand as the infants calvaria grow and thereby facilitate a progressive, normalization and rounding of the infants occiput.