Nothing's better than receiving unconditional love from your own sibling.

After Jamie Lynn Spears announced her pregnancy on Sunday (December 24) via Instagram, her big sister Britney Spears congratulated her on Twitter.

The "Oops! I Did It Again" singer quoted her sister's tweet and expressed her excitement for their new addition to the family.

“Maddie is going to be the best big sister!!!" she tweeted. So happy for you @jamielynnspears!!!! Love you all sooo much!!"

This will be Jamie Lynn's first child with husband Jamie Watson following her 9-year-old daughter Maddie with ex-fiancé Casey Aldridge.

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