Ryan D. Marler, 36, of O’Fallon, died on Thursday, Oct. 22, 2020 in O’Fallon. Visitation will be held form 3-8 p.m. on Monday, Oct. 26 at Kassly Mortuary, Ltd. in Fairview Heights. The funeral service will be held at noon on Tuesday, Oct. 27 with Reverend Ken York officiating. Interment will be at Jefferson Barracks National Cemetery in St. Louis, Missouri.