The actors, who are filming the "Ghostbusters" reboot movie in Boston, visited the hospital after some children put a sign on the windows which spelt "Who ya gonna call?", reported E! Online.
"They were so kind to all the kids and their parents. They took their time in each room visiting children as young as a few months to teens," Brooke Hynes, of Tufts Medical Center said.
The stars, who were in full movie attire with matching backpacks and ghost-fighting props, made the rounds visiting patients, their families, and posing for photographs.
Directed by Paul Feig, "Ghostbuster" also stars Chris Hemsworth, Michael K Williams and Neil Casey.
The film is scheduled to release on July 22, 2016.