Obama shared an adorable throwback picture to celebrate Michelle's 55th birthday

• Michelle Obama celebrated her 55th birthday on Thursday.
• In a touching post on Twitter, her husband, former President Barack Obama, shared a throwback of the two of them early on in their relationship.

Barack Obama toasted his wife on her 55th birthday with a touching tribute on Twitter.

The former president shared a throwback picture of him and Michelle from early on in their relationship.

A young Michelle beams as Barack puts his arm around her, holding a newspaper.

"I knew it way back then and I'm absolutely convinced of it today — you're one of a kind, @MichelleObama. Happy birthday!" Obama wrote in the post.

The couple celebrated their 26th wedding anniversary back in October. In her new memoir, "Becoming," Michelle details how her marriage to Obama was unlikely — he made a terrible first impression and she was against dating him, since they met when he was an intern at the Chicago law firm where she worked.

• Read more about the Obamas:
• Everything you need to know about Barack and Michelle Obama's love story — from the law office to the Oval Office
• 50 romantic photos show why everyone misses Barack and Michelle Obama
• This one quote reveals the secret to the Obamas' extraordinary 25 years together
• Barack Obama's sweet anniversary message to Michelle brought her to tears — and the Internet is gushing over it

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