Britney Spears Posts Throwback Photo With Jamie Lynn & Justin Timberlake for Sister's Birthday - Billboard

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Britney Spears attends the 29th Annual GLAAD Media Awards at The Beverly Hilton Hotel on April 12, 2018 in Beverly Hills, California.

Britney Spears went way back in the photo archives to wish her sister, Jamie Lynn, a belated happy birthday!

"Happy belated birthday to this beautiful soul!!!" Spears wrote in the photo caption to her little sister, who celebrated her birthday on April 4!

Jamie Lynn responded with a collection of cute emojis, while most of the other comments left on the post focused on Timberlake's unexpected appearance on Spears' Instagram feed

See the birthday post on Spears' Instagram account here

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