Flash mob videos are in some way all about one thing — surprising someone, or the world at large, with just how many people care about a given person, cause, or theme. It felt like perhaps the Web had seen them all, like the art form was getting stale.

But then a video like "A Flash Mob for Amy!" comes along, and you are surprised that they can still be affecting, even deeply moving. Amy was diagnosed with ovarian cancer in 2012, and after treatment and surgery, she appeared to be in the clear. But last October, Amy received the tragic news from doctors that the cancer was back and this time was not responding to chemotherapy. Her diagnosis was that the disease would be terminal.

While many people and their families would be justifiably devastated and find it difficult to enjoy life after such terrible news, Amy prefers a different path. One of her favorite phrases is (in Latin) "Dum vivimus vivamus," which means, "While we live, let us live." The spirit of this is evident in the surprise flash mob her family arranged.

In the video, a few of Amy's family members lead her to a chair in the backyard, and she is clearly aware that a surprise is on the way. Music starts playing, and her immediate family begins dancing. Then, a few more people appear out of nowhere, then a few more, and suddenly many more, all in rhythm to "Best of My Love" by The Emotions. All told, 50 people from five different states showed up to support and share their love with Amy, a clear testament to how many lives she has positively changed. Seeing her reaction shows just how much it means to her, and how much she is "living while she lives."

In the end, they embrace. The video, uploaded by Christina Noellsch on Vimeo, is a huge hit with viewers, who have posted comments like, "smiling from ear to ear. this is lovely," and, "Amy, never have a doubt that you are very much loved." The flash mob might be a well-worn video genre, but it can still bring a tear (or a lot of tears) to one's eyes.

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