SIOUX FALLS, S.D. (AP) — A Minnesota toddler who fell from a South Dakota hotel’s third-floor window has died.

Kathryn and Alex Hein of Lakefield, Minnesota, wrote in a Facebook post that their year-old son, Madden, died Monday, two days after falling at Club House Hotel & Suites in Sioux Falls.

“It is with heavy hearts to say that our sweet baby boy Madden gained his angel wings late on April 15th,” the couple wrote. “Madden is going into organ donation. His organs are going to help so many other people. Our little boy is a real-life superhero.”

Police are investigating the boy’s death, but a Sioux Falls Police Department spokesman, Officer Sam Clemens, told the Minneapolis Star Tribune that there is “nothing to lead us to believe it was anything other than a tragic accident.”

Alex Hein is middle school social studies teacher and a high school basketball coach. Kathryn Hein is a kindergarten teacher and helps coach volleyball. The couple also have a 3-year-old daughter and are expecting another child in August, the Star Tribune reported.