A father and son were playing catch on a Lake Michigan sandbar over the Fourth of July holiday weekend when everything went wrong, CBS News Chicago reports. David Meneou, 65, of Joliet, Ill., and Jameson Meneou, 20, of Lockport, Ill., died Saturday, July 5, officials said.

Candace Keller Meneou, David’s former wife and Jameson’s mother, told NBC affiliate WMAQ that the two victims were on a boat in Lake Michigan headed to Dune Acres near Indiana Dunes National Park. She added that David and Jameson, who had autism, were playing catch when, at some point, the ball was thrown overboard.