See How the Stars Celebrated Father's Day

From first-time dads Justin Timberlake and Ryan Reynolds to Caitlyn Jenner.

— -- The stars celebrated Father's Day Sunday by posting photos of themselves and the special dads in their lives.

FLEXIN' on Fathers Day," the singer wrote on Instagram, alongside a photo of him holding son Silas. "#HappyFathersDay to ALL of the Dads out there from the newest member of the Daddy Fraternity!!"

Fellow new dad Ryan Reynolds posed with his daughter James for a photo posted by wife Blake Lively.

"Happy Fathers Day!!! ... @vancityreynolds Since the day our baby was born, I've felt so strongly in my heart that you were most likely the father," the actress joked.

"Precious moments like this when we were traveling on tour with you are what I live for. You're such a good daddy to North & you will be the best daddy to our new son too!" she wrote on Instagram.

She also posted a throwback photo of West and North, writing: "I'm so lucky to be married to a man who is so in love with his daughter, your bond is so irreplaceable! Thank you for being such a good dad! We love and appreciate you so much! We're so blessed to have you!"

Other members of the Kardashian family were celebrating Caitlyn Jenner, formerly Bruce Jenner. Kylie Jenner wrote, "Happy Father's Day my little light of sunshine. 'You can still call me dad, Kylie. No matter what I'm always going to be your father. That's never going to change.'"

Kendall Jenner was equally touching: "my whole life this soul was my daddy and just because your appearance is different now doesn't mean you were any less of a father to me my entire life. happy Father's Day to the person who raised me, and taught me everything I know, my hero," she wrote.

"Nothing like father/daughter love. Happy Father's Day to you, CAJM ??????. Here is to all the engaged and present fathers, you create a backbone for society. We honor you all today," the Oscar winner wrote.

She also posted a photo of her around the same age with her own father, the late director Bruce Paltrow.

"A friend once said to me right after my father died, 'everyone has a father, but not everyone has a daddy,'" she wrote. "Brucie, you were both. To say that I miss you is an understatement. Happy Father's Day to you, wherever you are. You were the best of the best."

Meadow Walker, 16, also honored her late father, "Fast and Furious" star Paul Walker, with a throwback photo.

Singer John Legend celebrated his pops with a throwback photo. "Happy Father's Day to my awesome dad!" he wrote alongside the snap.

"Greatest man, and Dad, I know -- by far. I love you now more than ever," the younger Williams wrote. "Happy Father's Day, Dad. Thank you for being the Atticus to my Scout."

A photo posted by Gisele Bündchen (@giseleofficial) on Jun 21, 2015 at 5:31am PDT

"Nothing like father/daughter love. Happy Father's Day to you, CAJM ??????. Here is to all the engaged and present fathers, you create a backbone for society. We honor you all today," the Oscar winner wrote.

She also posted a photo of her around the same age with her own father, the late director Bruce Paltrow.

"A friend once said to me right after my father died, 'everyone has a father, but not everyone has a daddy,'" she wrote. "Brucie, you were both. To say that I miss you is an understatement. Happy Father's Day to you, wherever you are. You were the best of the best."

Meadow Walker, 16, also honored her late father, "Fast and Furious" star Paul Walker, with a throwback photo.

Singer John Legend celebrated his pops with a throwback photo. "Happy Father's Day to my awesome dad!" he wrote alongside the snap.

"Greatest man, and Dad, I know -- by far. I love you now more than ever," the younger Williams wrote. "Happy Father's Day, Dad. Thank you for being the Atticus to my Scout."