However, under the Kahn doctrine, to demonstrate a breach of this duty it must be shown that the owner or occupier of the land failed to take reasonable action to protect the trespasser against an unreasonable risk involving some inherent danger whose potential harm to the trespasser is reasonably foreseeable. ( Donehue v. Duvall, 41 Ill.2d 377, 243 N.E.2d 222; Sydenstricker v. Chicago Northwestern Ry. Co., 107 Ill. App.2d 427, 247 N.E.2d 15.) The owner or occupier of property is not required to indemnify against every possibility of injury. Driscoll v. Rasmussen Corp., 35 Ill.2d 74, 219 N.E.2d 483; Colon v. Marzec, 115 Ill. App.2d 410, 253 N.E.2d 669. A number of cases dealing with children injured while trespassing on a defendant's property under the Kahn doctrine have discussed whether the instrumentality causing the injury presented an unreasonable risk.

In fact, this court held more than 40 years ago that a railroad owes no duty to a 9 year-old boy who fell from the side ladder of a nonmoving railroad car located in defendant's unfenced railroad yard. Sydenstricker v. Chicago & Northwestern Railway Co., 107 Ill. App. 2d 427, 433-34 (1969). ¶ 23 Plaintiff relies heavily upon Nelson v. Northeast Illinois Regional Commuter Railroad Corp., d/b/a Metra, 364 Ill. App. 3d 181 (2006) in arguing that the frequent trespasser doctrine imposes a duty on the defendant railroad separate and apart from the holding in Choate. The issue in Nelson was whether Metra owed a duty of care under the frequent trespasser doctrine to a 15 year-old girl who was injured by a train as she crossed a railroad track.

Finally, we note that several other cases also support the premise that there can be no recovery if children of a similar age and experience as the plaintiff are capable of understanding the danger involved. See, e.g., Newby v. Lake Zurich Community Unit, District 95 (1985), 136 Ill. App.3d 92, 98, 482 N.E.2d 1061, 1066; Sydenstricker v. Chicago Northwestern Ry. Co. (1969), 107 Ill. App.2d 427, 433, 247 N.E.2d 15, 18. • 6 In light of the above-cited authority, the basis of the confusion attending the framing of the issues instruction in this case is readily apparent.

A prerequisite for the imposition of liability under Kahn is that the minor plaintiff be found to be "incapable of appreciating the risk involved" by reason of his immaturity. ( Kahn v. James Burton Co. (1955), 5 Ill.2d 614, 625, 126 N.E.2d 836.) City cites Sydenstricker v. Chicago Northwestern Ry. Co. (1969), 107 Ill. App.2d 427, 247 N.E.2d 15, for the proposition that where a child is capable of appreciating the risk involved in a particular activity, the application of Kahn is inappropriate. According to defendant the jury's finding that plaintiff was 18% at fault "conclusively determined that plaintiff was able to and did, in fact, appreciate the risk involved in attempting to jump on a moving freight train."

One of the requirements for liability under Kahn is that a child, because of his age and immaturity, be incapable of appreciating the risk involved. ( Sydensticker v. Chicago N.W. Ry. Co. (1969), 107 Ill. App.2d 427, 247 N.E.2d 15.) The risk involved in the present case was the simple and obvious danger of falling from the tree. In Sydensticker, the court upheld a summary judgment in favor of the defendant where a 9-year-old child fell from a non-defective ladder attached to a railway tank-car which was positioned on defendant's unfenced property in the normal course of defendant's business.

[5] The risk that children will climb upon and fall from an admittedly nondefective standard playground slide is not an "unreasonable risk" so as to produce a duty within the meaning of Kahn to require defendant to fence, guard or supervise the playground slide or warn plaintiff against its use. See Sydenstricker v. Chicago North Western Ry. Co., 107 Ill. App.2d 427, 247 N.E.2d 15 (1969). We therefore affirm the judgment.

These questions have been before American courts in a myriad of situations. See: 145 ALR, Annotated, p 322; 16 ALR3d, Annotated, p 1; Green Landowner's Responsibility to Children, 27 Tex L Rev 1 (1948). Recently, in Sydenstricker v. Chicago and N.W. Ry. Co., 107 Ill. App.2d 427, 247 N.E.2d 15, we passed on a variant of these recurring questions. We held that risk of a child climbing and falling from a nondefective stationary object lawfully located for an appropriate and useful purpose, was not unreasonable. Under such a circumstance, a landowner is not liable for injuries suffered by the child.