I don't have much information on this one. There's a good chance you may have already seen it. It's been floating around Facebook for a week or more. I think it's good enough to watch again.
I love the strength in the voice of the initial singer and the clear, pretty tone of the final singer at the end. And I love, love, love how so many people who are not part of the group join in the singing.
Grab a tissue if you are at all sentimental.