Elton John Pens Letter to His Sons for 75th Birthday: 'Just Be You — Fully and Completely You'

Elton John is reminding his sons of his life lessons in honor of his 75th birthday.

On Friday, the "Rocket Man" singer celebrated his significant milestone by writing a letter to his sons — Zachary, 11, and Elijah, 9 — whom he shares with husband David Furnish.

As he published the note in Time Magazine, John shared some sweet family memories of when he and Furnish, 59, took their children to see him perform live for the first time.

"We were in Las Vegas in 2018, and your Papa brought you to the show," he wrote. "You were amazed by it all, the lights and the costumes and the crowd. Afterward, you both said: 'I didn't know Daddy could do that.' "

John also shared the experiences of his younger self in the letter, saying he "didn't know I could do it, either."

"You're 11 and 9 years old now, and when I was your age, I could never have dreamed where life would take me," John said. "Looking back over the past 75 years, there is so much I am proud of, so much I have learned."

The legendary piano man continued, "When I was young, I was told to fit in, to do what others expected even when it didn't feel right. Now I realize I can only be me. Being true to myself is what gave me my voice, and helped me face my greatest fears."

As a result of his authenticity, John said he was able to forge "deep friends, found the love of my life and became your Daddy."

"Whoever you grow up to be, just be you — fully and completely you," he noted.

John and his husband first began dating in 1993 before he popped the question in May 2005. The couple had their first child Zachary in December 2010 and welcomed Elijah through the same surrogate in 2013.

In the letter, the "I'm Still Standing" crooner touched upon how he and Furnish "felt safe" to bring the kids into the world as "the children of two daddies," even though sometimes they admitted to having still feared other kids teasing theirs.

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"So we read you bedtime stories about families that looked like ours," he continued before adding their kids' favorite was The Family Book by Todd Parr. "You both immediately understood its simple message. 'There are lots of different ways to be a family,' it said. 'Your family is special no matter what kind it is.' "

"By the time you started school, you knew that we were different. You knew that different was okay, and most importantly, you knew you were loved," John added.

Additionally, the English icon also wrote about the challenges the LGBT community still faces, including the recent Florida "Don't Say Gay Bill," which he said could prevent kids who struggle "to understand and accept who they are" from getting the help they need.

"No child should have to live through this. I want you to grow up in a world free from conflict, where you can fulfill your dreams, whatever they may be," he explained.

To conclude the letter, John called his sons the "greatest gifts I have ever been given."

"You have filled my heart with love and my life with purpose and meaning in ways I didn't think were possible," he said. "You are my proudest achievements and I love you both so, so much."