Am I Liable For What Happens To The Neighbor's Toddler If They Enter My Apartment From Our Shared Balcony?

Location: Ohio, US

My apartment shares a balcony with 3 other apartments, some of which have children. One of those children is old enough to walk, but still in a diaper and isn't speaking as far as i can tell. Last year before it cold, and this year as soon as it got warm, this kid has been allowed to wander freely up and down the shared balcony, and has no qualms about staring into our living room. The balcony door is the only "window" on that side of the apartment so we like to keep the door open for ventilation, but the screen door can't lock and is very easy to open. We ourselves are child-free adults who do adult things in our apartment, which is far from childproof. It's getting increasingly difficult not to imagine the kid wandering in while I'm in the bathroom or something, and before I even know something's up they're in here getting into drugs, or have grabbed a knife, or whatever else we've left lying around. Do I have to start childproofing my home? Or is this more a "Call CPS" scenario?

Ideally we'd erect some kind of barrier separating our portion of the balcony from the neighbors', which is already approved by the landlord (some in the same apartment complex already have this). But that's been a low priority for us given the other demands on our time and money, and in the meantime that kid's out there for several hours most days. I do not want to be responsible for a child coming to harm, nor do I want to face any legal repercussions for negligent parenting on my neighbors' part. But I also like a cool breeze on a spring day.