Leonardo DiCaprio might be dating a 21-year-old, but rest assured that he still has some room in his heart for the more elderly among us, too—or, at the very least, for one 85-year-old in particular. Over the past few years, the 44-year-old actor has repeatedly demonstrated his unwavering devotion to the primatologist Jane Goodall—something that even the editors of the Time 100 apparently haven't failed to notice.

And on Wednesday morning, upon the release of the list's 2019 edition, it turns out that its organizers helped DiCaprio take the relationship to another level. Rather than explain each person significance themselves, they enlisted an additional 100 celebrities to do so—including, of course, DiCaprio, who stepped up to the plate to write an essay about Goodall. (This isn't the first time the famously press-shy actor has made an exception for her: Goodall is also practically the only person who can get him to pose for photographers.)

If you're wondering how, exactly, Goodall has managed to fully capture Leo's heart, allow him to tell you: Having read books both written about and by her, and familiarized himself with how the research she performed in Tanzania, when in her twenties, "ended up changing behavioral science forever," his admiration for the primatologist stretches back to long before they first met. Of course, since that happy day rolled around, his respect for her has grown exponentially: "It was only when I got to spend more time with Jane a few years ago that I truly felt I was in the presence of one of the most impactful and important leaders on the planet," he writes.

It's no surprise, then, that the 44-year-old actor has made a point to repeatedly hang out with the 85-year-old since then. In 2016, for example, they sat side by side at the United Nations; in 2017, DiCaprio attended (and even posed on the red carpet for) the premiere of the documentary Jane, which is about Goodall; and in 2018, DiCaprio invited Goodall to join him onstage at his namesake foundation's gala. Oh, and they've also hung out with Mark Ruffalo, not to mention Goodall's stuffed monkey, Mr. H.

Messengers of Peace Jane Goodall, Leonardo DiCaprio, and Stevie Wonder at the General Assembly on International Day of Peace at U.N. headquarters, New York.

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Leonardo DiCaprio and Jane Goodall speaking at the Leonardo DiCaprio Foundation Gala at Jackson Park Ranch in Santa Rosa, California, September 2018.

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Leonardo DiCaprio and Jane Goodall at the Peace Bell Ceremony on the occasion of the 35th Anniversary of the International Day of Peace at the United Nations in New York, September 2016.

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Mark Ruffalo, Jane Goodall, and Leonardo DiCaprio at the Leonardo DiCaprio Foundation Gala at Jackson Park Ranch in Santa Rosa, California, September 2018.

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They might look like an odd couple, but the pair has more in common than you may think: Both are jet-setters (Goodall still travels around the world 300 days a year); and both have plenty of experience with appearing on-screen. (The first documentary about Goodall was made in 1963, and, as she told W in 2017, they've been "nonstop" ever since.) Thanks to their work in environmental conservation, both also hold the title of United Nations Messenger of Peace. Plus, DiCaprio doesn't even think she's that old; in his essay, he describes her as being "at the young age of 85."

DiCaprio hasn't just come to consider Goodall "a very good friend" for whom he's "forever grateful"; thanks to her lifetime commitment to environmental protection, her philanthropy, and her optimism, she's also someone who "mesmerize[s]" him. According to DiCaprio, that's true of anyone who's heard her story or heard her speak, but no worries, Leo, we get the subtext: You'll always and forever be her greatest stan.

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