 In addition, affected infants may have heart defects.Osteodysplasties or bone abnormalities may be severe enough to become fatal in as little as 10 weeks of age, making lethality extremely common during infancy.Defects include cleidocranial dysplasia as abnormal bone development through hypoplastic (absent) clavicles, induced macrocrania (abnormal increase of skull), and diastasis (separation) of sutures.