Yes, Logan can actually move the car with her on top. He really does have fun, even though it doesn't look like it.
And yes, Izzy can move the car with Jacob on top of it.
Some of you may think I'm a terrible parent for allowing such dangerous behavior. In my defense, I say this: they are having fun, they are not fighting, and we've only had one fall. Izzy fell on her butt, but didn't hurt herself, so I don't think it counts. She only laughed harder. Just thought you'd enjoy a glimpse into daily life.