Ahead of "Captain America: Civil War's" release next week, Robert Downey Jr. has returned to children's hospitals to visit young fans with serious illnesses -- most recently making a stop at the Great Ormond Street Hospital (GOSH) in London, England.

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Among the fans he met, Downey Jr. was introduced 7-year-old Ethan Miller from Southend, Essex, who suffers from a rare blood disease, called ITP, and type 1 diabetes. Miller is just one of many ill fans that Downey Jr. has taken the time to get to know over the years.

Here's a photo of Miller in his Iron Man costume, posing alongside Downey Jr.:

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Directed by Joe and Anthony Russo and starring Chris Evans, Robert Downey Jr., Scarlett Johansson, Anthony Mackie, Sebastian Stan and more, "Captain America: Civil War" opens on May 6, 2016.

(via EntertainmentWeekly)