Britney Spears Wishes Sister Jamie Lynn a Happy Birthday With Sweet Throwback Pic

The former Nickelodeon star turned 26 on Tuesday.

Happy birthday, Jamie Lynn Spears!

The former Nickelodeon star turned 26 on Tuesday, and her big sister, Britney Spears, couldn't help but celebrate!

WATCH: Britney and Jamie Lynn Spears Look Happy at Disney World a Month After Maddie's ATV Accident

Brit Brit took to Twitter to wish her "angel" of a sister a happy birthday, alongside a sweet throwback pic of the two with their brother, Bryan.

"Happy birthday to my baby sister @jamielynnspears ???," she wrote alongside the snap. "She's an angel!!"

WATCH: Britney Spears Says Niece Maddie Is 'Making Progress' After Hospitalization: 'Let's All Keep Praying'

Jamie Lynn and her family appear to be doing well as her 8-year-old daughter, Maddie, has made a full recovery following her scary ATV accident in February. 

The singer took to Instagram last month to thank fans for their support as she shared a new pic of Maddie smiling from ear to ear.

"A month ago, at this time, I was living a mother's/anyone's worst nightmare happening right in front of my eyes, helplessly," she wrote. "I'll never stop thanking each of you for your prayers, because we recognize the miracle it created. We are beyond blessed, and we will NEVER forget y'all, and God's unbelievable mercy. #Godisgood."

WATCH: Jamie Lynn Spears' Daughter Maddie Returns to Basketball Practice Following Terrifying ATV Accident

See more in the video below.