[wideminded]

How do you ever forget your child is with you? How?

1. Car seats are supposed to be in the back and are sometimes rear-facing.
2. Sleeping babies are totally silent and car rides make them sleep.
3. Change of normal daily routine, e.g. different parent is supposed to drive or drop off kids.
4. Parent has other things on their mind.
5. Long enough drive for parent to be thinking about #4, forget about #3, and not be reminded because of #1 and #2.

There must be a lot of close calls, where the parent forgets but remembers before it's too late or someone else notices the kids.

[Jrabbit]

Please tell me you have no kids....

[Jay Thomas]

I don’t have kids. I simply cannot fathom how someone could “forget” the kids are in the car.

Your list provides no answer.