We describe two patients, a father and his daughter, with the cerebro-costo-mandibular syndrome. New manifestations not previously described include microstomia, long philtrum, posterior cervical skin fold, short internipple distance, and depressed sacral region. The presence of hydrocephaly in the proposita and spina bifida in the father may be other manifestations of neuraxial involvement in this syndrome. The first intrauterine ultrasonographic documentation of this syndrome showed polyhydramnios and, especially, the very unusual shape of the ribs, which were short and defective. Most characteristics of the pedigree point to autosomal dominant inheritance. The great variability of inheritance and expressivity of the very few documented familial cases described in the literature, together with the great frequency of sporadic cases, indicates genetic heterogeneity of this syndrome.