Britney Spears is beaming over her younger sister's engagement.
"So excited and happy for my sister, congrats @jamielynnspears - love you," the pop star Tweeted.
As previously reported on AccessHollywood.com, Jamie Lynn Spears, 21, announced her engagement to boyfriend Jamie Watson, 30, via Instagram on Saturday.
"Guesssss what??????" she captioned a photo of her now-fiance and herself holding up her left hand to reveal her new sparkler.
She later added a close-up shot of her beautiful diamond ring with the caption, "He did good."
This will be the first marriage for the former "Zoey 101" actress.
Jamie Lynn has a 4-year-old daughter, Maddie, from her previous relationship with Casey Aldridge, whom she split from in 2010.
-- Jesse Spero
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