💚“The man who taught us to love Earth…” — Prince William and Robert Irwin lead emotional tributes to David Attenborough on his 100th birthday — with heartfelt messages that are moving fans around the world

Prince William is leading the birthday wishes for TV icon Sir David Attenborough as he turned 100 on May 8.

In a new video filmed at Windsor Castle for his environmental initiative, Earthshot Prize, William, 43, said, “Happy 100^th David. I can’t believe it’s your 100^th birthday. Thank you so much for your support for the Earthshot Prize.”

“Everything you do continues to inspire me … Have a very happy day,” William added.

Sir David — who made his name decades ago creating groundbreaking documentaries capturing the natural and wild world — is one of the founding Earthshot Prize council members. The council helps shortlist, and ultimately choose, candidates to receive prize money from William’s organization. Now in its sixth year, Earthshot Prize works to find solutions to the environmental damage the planet has endured.

Another leading supporter is Australian TV personality and conservationist Robert Irwin, who also appeared in the video for Sir David’s milestone birthday.

Earlier this week, Irwin, 22, revealed that the children of William and his wife Kate Middleton had chosen a name for a new baby kangaroo at his Australia Zoo in Queensland.

He says of Sir David, who is the brother of late double Oscar winner Richard Attenborough, “Thank you so much for inspiring me and generations to have deeper understanding and connection to what’s most important — our beautiful natural world.”

In the birthday video, the man himself is quoted from a collection of Earthshot Prize speeches and his own broadcasts.”I have witnessed the natural world is all its splendor. We face a series of unprecedented challenges to nature and life on earth. If we put our minds to it, I believe we can live both well and responsibly on our planet.”

Earthshot Prize added in the caption of the Instagram post, “For decades, you’ve opened our eyes to the beauty and fragility of our planet, turning hope into action, and inspiring generations of changemakers.”

Sir David has been close with King Charles and the royal family for decades, and the official Royal Family social media sites also added their best wishes for his centenary — complete with images of him with a young Charles and his sister Princess Anne.

Overnight, William’s brother Prince Harry added his own tribute with an essay for Time magazine. In it, the 41-year-old wrote, “For almost anyone who grew up in the United Kingdom, Sir David Attenborough is more than a broadcaster; he is a secular saint,” Harry wrote. “He is an institutional pillar as essential to the national fabric as a cup of tea.”

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“He has earned the world’s trust by simply showing us that our environment is worth appreciating,” Harry continued. “He didn’t demand our attention, but drew us in with the wonder of nature all the same.”

“When a man who has quite literally seen it all begins to describe the loss of the planet’s stability, he isn’t being provocative,” Harry added. “He is reporting from the front lines of a planet he has known longer, and more intimately, than almost anyone alive.”

Later, on May 8, Sir David is expected at a special celebration of his life and work at a concert and show, also starring comedian and travel documentary maker Michael Palin and explorer Steve Backshall, at the Royal Albert Hall in London. It airs from 3.30pm ET/8.30 p.m. U.K. time.