These conditions results from enlargement of the tonsils and adenoids causing an obstruction to breathing, particularly at night. When lying flat, the airway can collapse in due to the large size of the tonsils & adenoids. 

Sleep apnoea refers to a cessation of breathing, which strains the heart & lungs and can result in poor sleep. If severe and untreated, these problems can lead to disruptive behaviour and tiredness at school; limit exercise tolerance; cause adverse changes to dental and facial bone development; & pre-dispose to a variety of ailments including hypertension, headaches and metabolic disorders.