2023 Mercedes-Benz E-Class ENGINE,FUEL/PROPULSION SYSTEM

I purchased an E450 Mercedes before reaching my first service appointment while driving my two daughters home from school the car began to shake uncontrollably, lost power, and then the engine light and oil lights came on. The car was towed to the manufacturer dealership for repair. It was determined that the piston number four was broken and the engine needed to be completely replaced. Less than two months after having the entire engine replaced the car broke down again with a similar shaking. This time one of my children and their friend were in the vehicle with me. The car was towed back to the dealership where they said the fuel pump went out and needed to be replaced. When I arrived to pick up the car, the technician pulling the car around noticed the shaking and the engine light on again. I did not leave in the car. The dealer kept the car to further investigate why the engine light was on again. Two days later they called to say they’d been driving the car around to “air it out” as air must have been trapped in the fuel system and that nothing further needed to be done. I am not confident that this vehicle is safe to drive or properly repaired. I’m also not confident that this vehicle doesn’t have other unknown issues that will arise overtime. It’s unsafe to drive children in this car. I still have not even reached 10,000 miles on this car.