Posting a throwback pic of the former president with young Malia and Sasha, Michelle wrote: "Happy #FathersDay @BarackObama. Our daughters may be older and taller now, but they’ll always be your little girls. We love you."
"Of all that I've done in my life, I'm most proud to be Sasha and Malia's dad. To all those lucky enough to be a dad, Happy Father's Day!"
Barack added, sharing the same photo.
Of all that I've done in my life, I'm most proud to be Sasha and Malia's dad. To all those lucky enough to be a dad, Happy Father's Day! https://t.co/ya1YAJignC
Michael Phelps might be a record-breaking Olympic athlete to the rest of us, but to Nicole Phelps and 1-year-old Boomer, he is a much-loved husband and father -- and they took to social media to let him know it!
Captioning a sweet throwback pic of Boomer on his dad's shoulders, Nicole wrote on Instagram:
"Happy Fathers Day @m_phelps00 I couldn't have asked for a better partner to build a family with. Watching you be a daddy to Boomer, Juno & Legend puts a smile on my face everyday. My heart is filled with love and happiness...thank you."
Despite still being a toddler, Boomer is already an Instagram star -- and he showed off his winning ways with his dad. Captioning a photo featuring the father-son combo in a video game bonding moment, Boomer "wrote": "I have the BEST dad ever!! I Love being able to sit and hang with him!! Even if it's when I'm beating him in some games!! #lookdadiwin #happyfathersday."
Chrissy Teigen also had a lot to say about her husband, John Legend, and how he's changed with fatherhood, captioning a pic of the "All Of Me" singer in a tuxedo.
"I took this photo right after John won his Tony a couple weeks ago. In all our time together (11ish years!!?!?) I cannot believe how much he has grown as a man and a husband," she wrote. "To see him go from big goals to big ideas to big wins and the love of so many makes me so so happy. 10 years ago, I didn't think he could get better, then I got to see him as a father. I don't know how or why Luna, my family and I got so lucky in this life but I will stop questioning and just be grateful. I love you so much, John. Happy Father's Day."
Ryan Reynolds, who is the father of two daughters, also celebrated the holiday with a hilarious joke, posting a photo of Sean Connery dressed in his famously terrible costume from the 1974 cult sci-fi drama Zardoz.
"Happy Father's Day, Dad," the 40-year-old Deadpool star captioned the photo. "You were always so hard to shop for."
Ayesha Curry, wife of newly-minted NBA champ Steph Curry, took to Instagram to share a few heartwarming snapshots of the proud dad with their adorable daughters -- 4-year-old Riley and 1-year-old Ryan.
"Happy Father's Day my love," she captioned the sweet slideshow. "You inspire, encourage, love and uplift our girls every single day! I couldn't have asked for a better dada for our little girls. We are so blessed to have you as the head of our home, center of our world, and keeper of our hearts. There is no one like you. We love you so much my darling. Blessed beyond words."
Miley Cyrus opted to share a cute flashback photo to celebrate the special day. The pic, from when she was a baby showed her dad, country star Billy Ray Cyrus, holding her in his arms while sporting a sleeveless black tank top and a particularly spectacular mullet.
"Happy Daddy's Day to my #1 Dude!" the 24-year-old "Malibu" singer wrote. "Love you so much."