40 ILCS 5/7-145.2
In lieu of the survivor's benefits otherwise payable under this Article, the spouse or eligible child of any deceased elected county officer who (1) had elected to participate in the Fund, and (2) was either making additional optional contributions in accordance with Section 7-145.1 on the date of death, or was receiving an annuity calculated under that Section at the time of death, may elect to receive an annuity beginning on the date of the elected county officer's death, provided that the spouse and officer must have been married on the date of the last termination of his or her service as an elected county officer and for a continuous period of at least one year immediately preceding his or her death.
The annuity shall be payable beginning on the date of the elected county officer's death if the spouse is then age 50 or over, or beginning at age 50 if the age of the spouse is less than 50 years. If a minor unmarried child or children of the county officer, under age 18, also survive, and the child or children are under the care of the eligible spouse, the annuity shall begin as of the date of death of the elected county officer without regard to the spouse's age.
The annuity to a spouse shall be 66 2/3% of the amount of retirement annuity earned by the elected county officer on the date of death, subject to a minimum payment of 10% of salary, provided that if an eligible spouse, regardless of age, has in his or her care at the date of death of the elected county officer any unmarried child or children of the county officer, under age 18, the minimum annuity shall be 30% of the elected officer's salary, plus 10% of salary on account of each minor child of the elected county officer, subject to a combined total payment on account of a spouse and minor children not to exceed 50% of the deceased officer's salary. In the event there shall be no spouse of the elected county officer surviving, or should a spouse remarry or die while eligible minor children still survive the elected county officer, each such child shall be entitled to an annuity equal to 20% of salary of the elected officer subject to a combined total payment on account of all such children not to exceed 50% of salary of the elected county officer. The salary to be used in the calculation of these benefits shall be the same as that prescribed for determining a retirement annuity as provided in Section 7-145.1.
Upon the death of an elected county officer occurring after termination of service or while in receipt of a retirement annuity, the combined total payment to a spouse and minor children, or to minor children alone if no eligible spouse survives, shall be limited to 75% of the amount of retirement annuity earned by the county officer.
Marriage of a child or attainment of age 18, whichever first occurs, shall render the child ineligible for further consideration in the payment of an annuity to a spouse or in the increase in the amount thereof. Upon attainment of ineligibility of the youngest minor child of the elected county officer, the annuity shall immediately revert to the amount payable upon death of an elected county officer leaving no minor children surviving him or her. If the spouse is under age 50 at such time, the annuity as revised shall be deferred until such age is attained. Remarriage of a widow or widower prior to attainment of age 55 shall disqualify the spouse from the receipt of an annuity.
40 ILCS 5/7-145.2