Here’s what Tom Holland learned from Robert Downey Jr.

"The amazing thing about RDJ is that he's arguably the most famous movie star on the planet, or the biggest movie star on the planet," Holland said while participating in a panel at a convention called FanX in Salt Lake City, Utah on Sep. 7, 2019. "But he's always early, he knows every crew member's name, he always knows his lines. He's professional, he's kind, he's caring."

The 23-year-old actor, who made his Marvel Cinematic Universe debut as Spider-Man/Peter Parker in 2016's "Captain America: Civil War," went on to say that Downey Jr. was immediately welcoming to him.

"I was sick on set one day and I didn't really know the guy," Holland said, adding that Downey Jr. invited him to his trailer and was comforting.

"He was really sweet and he kind of looked after me and took me under his wing a little bit," the "Spider-Man: Far From Home" star said. "Entering the Marvel Universe is daunting, it's a big process."

Robert Downey Jr. and Tom Holland in "Spider-Man: Homecoming."

(Sony Pictures Entertainment)

He added: "The thing I've learned most from him, and I've learned from [Chris] Hemsworth and [Chris] Evans and Scarlett [Johansson] and everyone really, is that just because you're at the top, doesn't mean you can be a d---."

Downey Jr.'s character, Iron Man/Tony Stark, acted as a mentor to Holland's young webslinger throughout the movies he has appeared in. Holland also revealed that he has the veteran actor's name saved as "The Godfather" in his phone and thought their friendship was over after he accidentally hung up on Downey Jr.

Despite Tony's heartbreaking death in 2019's "Endgame," the two stars have remained close. Amid news that Holland will be departing the MCU due to a deal between Sony and Marvel falling through, the actors met up to spend time together.

"We did it Mr Stark!" Holland captioned a series of photos of the stars taking selfies together, referencing a similar line that Peter said during Tony's final moments in "Endgame."

This article originally appeared on Insider. Follow @thisisinsider on Twitter.

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