EL CAJON, CA (CBS SF/AP) – The Avengers have teamed up to lift the spirits of a teenage fan with leukemia.

Iron Man Robert Downey Jr. joined Captain America Chris Evans to visit 18-year-old Ryan Wilcox at his home in Southern California on Monday.

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The trip was documented on Instagram by Gwyneth Paltrow, who plays Pepper Potts in the “Iron Man” films.

Students at Grossmont High School in suburban San Diego made a plea on Facebook this month asking the cast of “Captain America: Civil War” to visit Wilcox, saying it could be the best moment of his life. Evans responded with a video message telling Wilcox to “stay strong.”

Wilcox, a junior, has been at home for months battling leukemia.

He told the San Diego Union-Tribune that he was shocked by the visit.

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“I was like, ‘WHAT?!’ when I saw them,” Wilcox said. “I told them how much I liked them, and their movies. They asked me which one was my favorite…. They are so awesome. This was overwhelming. It was great.”

The celebrities signed his bedroom wall and gave him gifts from the Marvel film series, the boy’s mom, Amy Wilcox, told the newspaper. He posed with the trio — flashing a big smile and wearing a t-shirt depicting Captain America’s shield.

“It was so nice of them to take time out from their (lives) to do this,” Amy Wilcox said. “Gwyneth gave me the biggest hug, saying it was from one mom to another.”

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