We report a sister and brother with congenital heart defects, hamartomas of the tongue and polydactyly. Both had coarctation of the aorta, which was repaired in early infancy. In addition, the girl had atrioventricular canal. She died postoperatively at age 4 years. The boy had subaortic stenosis and died of pneumonia at age 2 years. Both children had normal psychomotor development. The parents were healthy and unrelated. The familial occurrence could be due to a previously unrecognized autosomal recessive syndrome or parental gonadal mosaicism for a dominant syndrome.