<prompt> Common causes of congenital stridor in child -Laryngeal webLaryngomalaciaHaemangiomaSubglottic stenosis  <response>: STRIDORDue to upper airway obstruction,Types -Inspiratory stridor - Obstruction above vocal cords supraglottic.Expiratory stridor - Obstriction distal trachea.Biphasic - From supragiottic or proximal tracheal.Causes Infective:Croup lanyngo tracheo bronchitisBacterial trachetisRetropharyngeal abscessCongenital:Laryngomalacia: 60 of all total most common cause.Vocal cord paralysis - 2nd most common.Subglottic stenosis - 3rd most common. Iatrogenic :Long-term intubation leads to subglottic stenosis - the most common causes of Acquired stridor in children.Neoplasm: Recurrent respiratory papilloma RRP MC a benign tumour and larynx. 