Cake fails are an important staple of web humor. But last week, one woman's less-than-perfect cake reminded her of the importance of kindness. Facebook user Lisa Sarber Aldrich posted a photo of her grocery-store cake with a messy-looking "Happy Birthday Mandy" written on top of it. Aldrich could have freaked over the poor penmanship, but instead she smiled and thanked the girl who had prepared the cake. As she checked out, Alrdrich learned just how appreciated her chill response was."One cashier put her arm on my shoulder," Aldrich explains in her Facebook post, "and said, 'The girl who wrote that has autism. Thank you for smiling and thanking her — even though she's not supposed to write on cakes, you probably made her day.' So I guess the moral of the story is that kindness is important."It's a great message, especially around the holidays, when we know stores will be crowded and workers will be stressed. It's easy to turn into a real-life villain who yells at a cashier while "Joy to the World" plays in the background. So keep in mind that you never know what's going on in other people's lives, and the best thing you can be is patient and kind.