Illinois Supreme Court Rule 191(a) (eff. Jan. 4, 2013) governs the admissibility of affidavits in support of a motion for summary judgment. This rule "provides that an affidavit must be (i) made on the affiant's personal knowledge, (ii) not consist of conclusions but facts admissible in evidence, and (iii) affirmatively show that the affiant could testify competently about those facts." Kreczko v. Triangle Package Machinery Co., 2016 IL App (1st) 151762, ¶ 18.
[T]he rule is satisfied if from the document as a whole it appears that the affidavit is based upon the personal knowledge of the affiant and there is a reasonable inference that the affiant could competently testify to its contents at trial." Burks Drywall, Inc. v. Washington Bank & Trust Co., 110 Ill. App. 3d 569, 576 (1982). Strict compliance with Rule 191(a) is necessary, and "[a]ffidavits in opposition to motions for summary judgment must consist of facts admissible in evidence as opposed to conclusions, and conclusory matters may not be considered in opposition to motions for summary judgment." Berke v. Manilow, 2016 IL App (1st) 150397, ¶ 21.