(750 ILCS 5/610.5)
(a) Unless by stipulation of the parties or except as provided in Section 603.10 of this Act, no motion to modify an order allocating parental decision-making responsibilities, not including parenting time, may be made earlier than 2 years after its date, unless the court permits it to be made on the basis of affidavits that there is reason to believe the child's present environment may endanger seriously his or her mental, moral, or physical health or significantly impair the child's emotional development. Parenting time may be modified at any time, without a showing of serious endangerment, upon a showing of changed circumstances that necessitates modification to serve the best interests of the child.
(c) Except in a case concerning the modification of any restriction of parental responsibilities under Section 603.10,
the court shall modify a parenting plan or allocation judgment when necessary to serve the child's best interests if the court finds, by a preponderance of the evidence, that on the basis of facts that have arisen since the entry of the existing parenting plan or allocation judgment or were not anticipated therein, a substantial change has occurred in the circumstances of the child or of either parent and that a modification is necessary to serve the child's best interests.
(d) The court shall modify a parenting plan or allocation judgment in accordance with a parental agreement, unless it finds that the modification is not in the child's best interests.
(e) The court may modify a parenting plan or allocation judgment without a showing of changed circumstances if (i) the modification is in the child's best interests; and (ii) any of the following are proven as to the modification:
(1) the modification reflects the actual arrangement
under which the child has been receiving care, without parental objection, for the 6 months preceding the filing of the petition for modification, provided that the arrangement is not the result of a parent's acquiescence resulting from circumstances that negated the parent's ability to give meaningful consent;
(2) the modification constitutes a minor modification
in the parenting plan or allocation judgment;
(3) the modification is necessary to modify an agreed
parenting plan or allocation judgment that the court would not have ordered or approved under Section 602.5 or 602.7 had the court been aware of the circumstances at the time of the order or approval; or
(4) the parties agree to the modification.
(f) Attorney's fees and costs shall be assessed against a party seeking
modification if the court finds that the modification action is vexatious or constitutes harassment. If the court finds that a parent has repeatedly filed frivolous motions for modification, the court may bar the parent from filing a motion for modification for a period of time.
(Source: P.A. 99-90, eff. 1-1-16; 99-763, eff. 1-1-17