Okay, how do you forget a full-sized adult in a hot van?

I have never understood people who apparently 'forget' their child in a hot car, leading to terrible tragedy. And people leave pets without really considering the heat. But how can a caretaker forget a 20-year-old autistic man they were supposed to be looking after? Did she assume he came on inside, even though she entered the building with just one person? Isn't there some sort of check-in process? It's not like it was a large group--she was responsible for two people, and lost one. But instead, he wasn't found missing for hours, and by then, it was too late. I hope the investigation can help keep such a tragedy from occurring again.

Autistic man dies after being left in hot van: Pa. police say temperatures reached 150 degrees inside vehicle

LANGHORNE, Pa. — An autistic young man who didn't speak was left in a scorching van at a residential treatment home, where his lifeless, overheated body was found more than five hours after his small group returned from an amusement park.

Brian Nevins, 20, was not deemed missing until a nurse looked for him to give him medication around 4 p.m. Saturday, as temperatures in suburban Philadelphia reached the high 90s. Nevins had returned with two other counselors and three other clients around noon from a brief trip to nearby Sesame Place.

Nevins was found in a parked van at Woods Services, a treatment home about 20 miles northeast of Philadelphia where the native New Yorker had lived since he was about 14.

His twin brother, also autistic, also lived at the center, authorities said. The surviving twin, who had not been on the outing, left the home with relatives after his brother's death, Middletown Township Detective Jeffry Sproehnle said.

The counselor responsible for Nevins on the trip also served as the van driver. She has been suspended, Sproehnle said. Woods Services did not return several calls seeking comment Tuesday.