"So excited and happy for my sister, congrats @jamielynnspears — love you," Britney tweeted out Monday morning.
Her tweet was in reaction to a couple of Instagram posts from the younger Spears on Sunday, when she shared the fact that boyfriend Jamie Watson had popped the question.
"Guesssss what??????" Jamie Lynn wrote to caption an all-smiles shot of herself flaunting a new ring on that finger, with 30-year-old Watson at her side.
Posting a brilliantly clear picture of a brilliant and big rock, the 21-year-old wrote on the second shot, "#hedidgood."
Marriage is something she and Watson had been thinking about for a while, he told the New York Post in January. They've been dating on and off for three years.
Jamie Lynn has a child, 4-year-old Maddie, with Casey Aldridge, to whom she was previously engaged.
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