The former President and First Lady of the United States met back in 1989, when the Becoming author, then 25, was assigned to mentor her future husband, then 28, at the Chicago law firm they worked at, Sidley Austin LLP.
The two went on to tie the knot on October 3, 1992, in Michelle's native Chicago, Illinois.
To commemorate their 31st anniversary, the former marketing and intellectual property lawyer took to Instagram to share a sweet tribute to her hubby.
She posted a candid photo of the two seemingly on vacation, where she is wearing her hair in braids, donning a printed knit dress and a smile on her face, cozying up next to her equally smiley husband, who is in a gray linen short-sleeve button-down shirt paired with white pants.
"31 years, and a lifetime to go," Michelle endearingly wrote in her caption, adding: "I love going through life with you by my side, @BarackObama. Happy anniversary, honey!" next to a red heart emoji.
Her followers were quick to take to the comments section under the post to gush about the sweet tribute, with Rita Wilson writing: "Happy Anniversary!!!!" as others followed suit with: "Happiest anniversary to our favorite couple on the planet!" and: "Happy anniversary to you both. God bless you both," as well as: "That's love right there in human form! Happy Anniversary," plus another one of her followers added: "Happy 31st Anniversary to my favorite President and First Lady. I hope you have a great day."
Obama also shared his own tribute on Instagram, posting a photo of the two while on a walk by the beach, both wearing coordinating blue jackets.
"Happy anniversary, sweetheart!" he wrote, adding: "You're brilliant, kind, funny, and beautiful – and I'm lucky to call you mine."
After their 1992 nuptials, the two went on to welcome two daughters: Malia, 25, and Sasha, 22; they both live in Los Angeles.
Obama first went into politics when he became a senator for Illinois' 13th district, a role he held from 1997 to 2004, before becoming a US Senator from 2005 until he became President in 2008, for two terms.
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