In Clown (2014 or 2016) by Eli Roth, we learn that the "Cloyne" must eat five children before it can leave its host. Later in the film, it demands that one of the protagonists bring it "one more child" or he'll instead consume their son, Jack.
The thing is, as best I could tell, he'd only killed three children so far:
The inquisitive child at the apartment complex, The bully, Colton and a child at Chuck E. Cheeses
"He sneaks into an indoor playground/arcade and devours two children" but I only saw the one.
Was there a fourth victim that I missed?