It's not ideal to take photographs of people with the sun shining brightly in their eyes, but sometimes it's necessary. Whether its you mother-in-law demanding that your group stand in front of the rhododendrons for an Easter photo or whatever, there is a way to help make sure faces aren't too scrunched and eyes aren't closed. It's really easy and works nearly every time.
Start by telling your subjects to close their eyes and relax their faces. Continue with "On the count of three, open your eyes." Just as you get to three, click your shutter button and you should catch the person with their eyes open.
They may still be a bit squinty, but at least they won't have scrunchy face!