In M.E.H. v. L.H., 177 Ill. 2d 207, 685 N.E.2d 335, 226 Ill. Dec. 232 (1997), our supreme court found that the defendant in that case had a vested right to invoke the limitations period as a defense and that the defendant's vested right could not be taken away without offending the due process protections of the state's constitution. M.E.H. 177 Ill. 2d at 214-15, 685 N.E.2d at 339. The court reached its decision only after first concluding that "once a statute of limitations has expired, the defendant has a vested right to invoke the bar of the limitations period as a defense to a cause of action. That right cannot be taken away by the legislature without offending the due process protections of our state's constitution." M.E.H., 177 Ill. 2d at 214-15, 685 N.E.2d at 339-40.