Phelan, P. D., Stocks, J. G., Williams, H. E., and Danks, D. M. (1973). Archives of Disease in Childhood, 48, 275. Familial occurrence of congenital laryngeal clefts. Two sibships of double first cousins in which 6 children had congenital laryngeal anomalies are reported. 3 of the children had proven congenital posterior laryngeal clefts, 1 had subglottic stenosis with a deformed cricoid cartil...