Chubby cheeks are a feature of plump characters and chubby babies. They are a relatively simple feature to add to any character's face. There are two ways to draw chubby cheeks, depending on what type of drawing you are doing. When doing a cartoon drawing, chubby cheeks are simply an extra shape under the eyes. When drawing more realistic characters, shading and highlighting are used.
Cartoon Cheeks
Draw a downward facing C-shape under one eye.
Draw another C-shape underneath the first. Make sure that the "C" is lighter than the first and that the opening to the "C" is facing upward.
Repeat steps 1 and 2 underneath the other eye.
Realistic Chubby Cheeks
Shade the area under the eyes so that the shading creates a C-shape that cups the eye.
Add a J-shape of shading from the outer edge of the nose to the hairline. The "J" should lay beside the bottom of the nose and the top of the lips and flare outward to the hairline to define a high cheekbone.
Shade the inner area of the "J" so that the shading forms a three-dimensional ball.
Erase a little shading from the top of the cheek for a highlight.