A happy family, playing airplane with the youngest daughter in their local park. Because of the child's age, we'll respect the family's privacy in these comments.
This image in particular highlights the strengths of the 135 mm f/2 L. The eyes are razor sharp, and at full-resolution the reflections of clouds are clearly deliniated ( thanks in this case to excellent autofocus ), the color is warm and saturated, but not cartoonish, and the bokeh, or out-of-focus background, particularly the in the highlights, is just beautiful. This is by far my favorite portrait lens.