Justin Timberlake says fatherhood is an honour.

The 37-year-old musician and his wife Jessica Biel welcomed his son Silas into the world in April 2015, and he has opened up on the bond he shares with his boy in a touching post for Father's Day on Sunday (17.06.18).

Alongside a series of touching snaps of the pair sharing some quality time together, he wrote: ''The last 3 years of my life have brought more joy than I could ever imagine. Being a father is such a trip... an amazing discovery every day.

''My son: it is my honor to be your Daddy. You make me feel a love that I didn't know existed.

''I will ALWAYS be there... to pick you up when you fall, to lift you up when you are ready to soar, and to remind you that your humility will be your guide through this thing called life. (sic)''

He also urged other dads to be the best role models, as he said that kids are becoming more aware, and listening to their parents ''more than we know.

He continued: ''And to all the Dads out there: Keep on keeping on! Our children are watching and listening more than we know! I'm celebrating you all today! Happy Father's Day! Cheers!''

His gushing message comes after Justin - who kicks off his European tour in Paris, France on July 3 - paid tribute to his wife and son during *Nsync's Hollywood Walk of Fame ceremony at the end of April.

He said at the time: ''Mom, thank you so much for being there. And now my beautiful wife, who's here today, is now the mother of our beautiful son. I love you so much.''