The swimming reflex is the combination of 2 unique factors. First, when submerged, babies will reflexively stop breathing through their nose. Secondly, their high voice boxes mean that any water will go into their .

Trachea

Explanation:

The laryngeal reflex occurs and it is present in babies after birth. When water occupies or enters the mouth, the laryngeal reaction is triggered. While your infant is underwater, the glottis and epiglottis shut, keeping water from penetrating the throat(larynx and pharynx) and establishing a watertight barrier to the lungs. This is so to prevent the aspiration of water into the lungs.