To understand earaches, and ear infections, you must first know about the Eustachian tube, a narrow channel connecting the inside of the ear to the back of the throat, just above the soft palate and uvula. The tube allows drainage of fluid from the middle ear, which prevents it from building up and bursting the thin ear drum. In a healthy ear, the fluid drains down the tube, assisted by tiny hair cells, and is swallowed. Children have Eustachian tubes that are shorter, more horizontal, and straighter than those of adults. These factors make the journey for the bacteria quick and relatively easy. It also makes it harder for the ears to clear the fluid, since it cannot drain with the help of gravity. A child's tube is also floppier, with a smaller opening that easily clogs.