The So You Think You Can Dance alum announced the news on her Instagram. Alongside a photo of the happy pair, Arnold wrote: "Just when I thought our day in Africa couldn't get any better.... We are engaged!!:):)" It's pretty obvious from the photo these two are absolutely glowing and oh-so-in-love.
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For his part, Cusick posted a very similar picture with a simple, yet effective, caption: "ENGAGED," he wrote alongside their very wide smiles.
BFF and fellow Dancing with the Stars dancer and So You Think You Can Dance contestant Witney Carson help spread the love with a post of her own. "My best friend in the whole entire world got engaged to the love of her life today! I am crying tears of joy, I could not be happier!! I love you guys, congrats!!! @lindsarnold @samcusick," she exclaimed alongside Cusick's picture of the two of them.
Sounds like this week was a good one for these two lovebirds. If we know once thing to be true about this wedding, there will be a ton of dancing (and good dancing, at that!). Congrats to the happy couple!