60 ILCS 1/15-10
Until the effective date of this amendatory Act of 1997, whenever a township is organized under this Article and any of the territory of the city not more than one-half square mile in extent and containing not more than 50 inhabitants is disconnected from the city, the county board may, by resolution, upon receiving a certified copy of the resolution or ordinance of the city disconnecting the territory and after a public hearing on the matter following notice given as provided in Section 15-5, disconnect the territory from the township and annex it to an adjacent township or townships.
Whenever a township is organized under this Article and any of the territory of the city is, after the effective date of this amendatory Act of 1997, disconnected from the city by court order or ordinance, the territory shall automatically be disconnected from the otherwise coterminous township and connected to the adjacent township, and the transfer of the territory shall not affect the city's status as a city with a coterminous township. If disconnection is pursuant to court order, the petitioning party in the cause shall, within 30 days of the entry of an order permitting disconnection, serve a copy of the order upon the coterminous township, the adjacent township, and the county clerk by certified mail, return receipt requested, and shall file proof of the service with the circuit clerk. Upon objection by either the coterminous township or the adjacent township within 180 days after the enactment of the ordinance or after service of the court order, the county board may, after receiving a certified copy of the court order or ordinance and after a public hearing on the matter following notice given as provided in Section 15-5, pass an ordinance annulling the automatic disconnection of territory from the coterminous township. The action by the county board shall not affect the disconnection of territory from the city, but shall cause the territory to remain in the coterminous township. The annulling by the county board of the automatic disconnection of territory from the coterminous township shall not affect the city's status as a city with a coterminous township.
60 ILCS 1/15-10