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And judging by the caption, the star has been able to keep the life-changing tidbit a secret for a week — even after dropping a hint about it on Tuesday. Michalka posted a shot of her and her sister at a concert with the sparkler in clear view accompanied with the caption, "Hmmm....no one's noticed yet. #Lookcloser."
After making the official announcement, Michalka tweeted, "Wanted to share the exciting news! Feel very blessed to know such a great love #engaged x Aly."
Ringer and Michalka, pictured above at a cozy dinner recently, just celebrated their one year and seven month anniversary.
This former Disney kid isn't a little girl anymore, and we can't wait to see her become a bride. Congrats to the happy couple!