Justin Timberlake and Ryan Reynolds were too cute as they celebrated their first Father's Day as dads. Both stars shared sweet snaps on Instagram -- and we couldn't love these proud papas any more than we do now!

Timberlake posted a photo with son Silas on Instagram with the caption, "FLEXIN' on Fathers Day...#HappyFathersDay to ALL of the Dads out there from the newest member of the Daddy Fraternity!!" We also love Silas' onesie, which had, "I Heart Dad," written on it.

Meanwhile, Blake Lively posted a hot pic of her hubby Ryan Reynolds, carrying their daughter James.

Along with the pic, the former Gossip Girl, "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 #ILoveYouSoMuchItsSilly."

Reynolds also took to Twitter to celebrate Daddy's Day, tweeting,"On Fathers Day, my daughter smiled at me. It was all the gift I needed as I packed a bag and left for 6 years to write a book on parenting."

Love these hot dads!