With the image open, drag the Background layer over the New Layer icon to duplicate it.

Click the Zoom tool and zoom in to enlarge the red eyes.

Click and hold the Spot Healing Brush tool to reveal its other tool options.

Click the Red Eye tool. The Options bar changes to show the options for the Red Eye tool.

Double-click here and type 15.

Make sure that the Darken Amount data field is set to 50.

Click in the red area of one eye. Photoshop replaces the red with a neutral gray.

Click in the red area of the other eye. Photoshop again replaces the red with a neutral gray.

Click the Zoom tool. The Options bar changes.

Click Fit Screen. Photoshop zooms out, so you can see the entire image and the more natural-looking eye color.