Cheerios is a cereal brand which Greg Heffley eats. In the book, they are in a box with "Cheerios" written in small letters. They are one of the few branded names used in the books. In the online version, when Greg gives Manny these in a bowl, Manny dumps them into his plastic potty. Also in The Third Wheel, the Cheerios are stuck between the seats.
- They are based on the real life cereal brand, Cheerios.