In Schwartz v. Swan, 63 Ill. App. 2d 148, 157-58, 211 N.E.2d 122 (1965), the plaintiff suffered injuries to her head, neck, shoulder, arms and back in a car collision. Another car collision 10 days later caused injuries to the same body parts. The plaintiff did not allege the extent to which each accident contributed to her injuries but claimed only that the injuries from the first accident were aggravated by the second accident. Schwartz, 63 Ill. App. 2d at 151-52. The Court determined that the medical evidence justified the joinder of the two actions for a single trial. Schwartz, 63 Ill. App. 2d at 160. It is the province of the fact finder to determine the extent to which each collision contributed to the nature and severity of the plaintiff's injuries. Schwartz, 63 Ill. App. 2d at 157-58. "The fact that it might be difficult, under these circumstances to establish the exact proportion of injury caused by each occurrence, is not sufficient reason to deprive plaintiff of the substantial right of a proper evaluation of her damages. To hold otherwise would require plaintiff to prosecute her claim in separate trials, in each of which the defense would argue the uncertainty of the injuries resulting from each occurrence." Schwartz, 63 Ill. App. 2d at 158.