Final answer:
The most common serious complication of AOM in children is otitis media with effusion (OME), leading to chronic ear infections due to blockage of the Eustachian tubes and accumulation of fluid in the middle ear.
Step-by-step explanation:
The most common serious complication of acute otitis media (AOM) in children is the blockage of the Eustachian tubes, leading to otitis media with effusion (OME). When the Eustachian tubes are blocked, fluid becomes trapped and accumulates in the middle ear. This not only causes discomfort and potential hearing issues but also provides an environment that fosters the growth of bacteria, possibly leading to recurring and chronic ear infections. Young children are especially prone to these complications because of their more frequent upper respiratory infections, the anatomical structure of their Eustachian tubes, and their common behaviors, such as bottle feeding while lying down.