Jamie Lynn Spears Engaged to Jamie Watson

Jamie Lynn Spears/Instagram

Although Britney Spears' engagement to former agent Jason Trawick ended less than two months ago, her younger sister announced her own engagement Saturday night.

Actress and singer Jamie Lynn Spears, 21, shared an Instagram picture of her diamond studded engagement ring, along with the caption: "Guessss what????"

She later posted ":) #hedidgood" and shared a photo of the happy couple.

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Spears and fiance Jamie Watson, 30, have reportedly been together on and off for three years. Watson told the New York Post Page Six in January the couple had discussed marriage and were trying to work things out.

Jamie Lynn Spears/Instagram

Spears has a 4-year-old daughter, Maddie, with ex-fiance Casey Aldridge.

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Thanks to her sister Britney's worldwide fame, Jamie Lynn has been in the limelight most of her life.

Spears made her acting debut in 2002 as a younger version of her sister in the Paramount Pictures film "Crossroads."

She then went on to perform as a regular in the eighth season of the sketch comedy series "All That" and starred as Zoey Brooks in the hit Nickelodeon scripted television series "Zoey 101." "Zoey 101? went on for four seasons.

She is currently working on her country music career in Nashville, Tenn.