Every type of legal claim has a deadline for filing suit, called the statute of limitations. The deadline starts running when the cause of action accrues. Usually when the injury happened, but sometimes when the plaintiff discovered the harm.
In Missouri, personal injury claims have a 5-year deadline. In Illinois, it's 2 years. Wrongful death is 3 years in Missouri, 2 in Illinois. Claims involving government defendants run on different clocks. In Illinois, 745 ILCS 10/8-101 gives one year to file suit against a local public entity, replacing the usual two years rather than adding to it. In Missouri, RSMo § 82.210 imposes a 90-day notice only on cities of 100,000 or more and only for defects in a street, sidewalk, or similar way.
Statutes of limitations are jurisdictional. A court has no authority to hear a case filed late, no matter how good the case is otherwise.