On Tuesday, the former first lady posted an Instagram photo showing the family posing near the ocean while on vacation.
While it is not clear what year the photo was taken, Sasha, 19, and Malia, 22, are much younger in the picture, which shows Barack holding his youngest daughter in his arms.
“Happy birthday to my favourite guy,” Michelle captioned the photo. “Here's to all the good days, blue skies, and new adventures to come.”
Numerous others joined in wishing the former president a happy birthday, including former presidential hopeful Pete Buttigieg and actor Billy Porter.
“Wishing a Happy Birthday to @BarackObama, who by his words, actions, and example, continues to remind America what true presidential leadership looks like,” the former Mayor of South Bend, Indiana, wrote.
Porter wrote: “Happy Birthday @BarackObama... You will always be one of my personal heroes. You are a light that continues to nurture the world with kindness and I thank you for planting seeds of hope wherever you go! Thank you for just being you! I salute you!”
Michelle’s birthday post comes after she revealed last week during the first episode of her new podcast The Michelle Obama Podcast, which featured Barack as a guest, why she had fallen in love with her husband.
“One of the reasons I fell in love with you is because you are guided by the principle that we are each other’s brother's and sister’s keepers,” she said of her husband of almost 28 years. “And that’s how I was raised.”