In the books, it’s mentioned that Sirius plays “a malicious prank on Snape by telling him about the Whomping Willow passageway, hoping that he would be terrified or even get seriously hurt by what he found at the other end. James, who hated Snape, was able to stop Snape and save his life in the nick of time, but Snape still uncovered Remus’s secret, seeing him at the end of the passage.” [X]……..I always wondered how Remus would have taken that.