820 ILCS 156/10: Leave.

(a) An employee of a large employer is entitled to use a maximum of 12 weeks of unpaid leave if the employee experiences the loss of a child by suicide or homicide.

(b) An employee of a small employer is entitled to use a maximum of 6 weeks of unpaid leave if the employee experiences the loss of a child by suicide or homicide.

(c) Leave under subsection (a) or (b) may be taken in a single continuous period or intermittently in increments of no less than 4 hours, but leave must be completed within one year after the employee notifies the employer of the loss.

(d) An employer may require reasonable advance notice of the employee's intention to take leave, unless providing such notice is not reasonable and practicable.

(e) An employer may require reasonable documentation. Documentation may include a death certificate, a published obituary, or written verification of death, burial, or memorial services from a mortuary, funeral home, burial society, crematorium, religious institution, or government agency. An employer may require that the documentation include the cause of death.