Tonsils in humans include, from superior to inferior: nasopharyngeal tonsils (also known as adenoids), palatine tonsils, and lingual tonsils.
en.wikipedia.org For children, the adenoids (also known as a pharyngeal tonsil or nasopharyngeal tonsil), are usually removed at the same time, a procedure called adenoidectomy, or tonsilloadenoidectomy, when combined.
en.wikipedia.org Just as the size of the adenoids is variable between individuals, so is the age at which adenoids atrophy.
en.wikipedia.org On the other, the size of the adenoids, and again by implication, any obstruction that they might be causing, also declines with increasing age.
en.wikipedia.org