Hi!
We have been making cars for children as young as 9 months. We used to use the Lightning McQueen car as well, but since it was discontinued, we have been these remote Lamborghini’s:
Amazon.com: Kidzone Ride On Car 12V Lamborghini Urus Kids Electric Vehicle Toy w/Parent Remote Control, Horn, Radio, Port, AUX, Spring Suspension, Opening Door, LED Light - White : Toys & Games
For our kiddos that are still too small to reach the steering wheels we frequently add pads behind their back or build PVC structures onto the steering wheel that they can hold onto but move the button closer.
Additionally, sometimes we make full PVC bars to move the button closer, you just have to be careful with these and make sure they can still get their legs into the footwell. Notably, we wire all our cars so that the child must hit their button and the parents must hit the button on the remote for the car to move (remote and button wired in serries). This wiring design allows for us to move the button and the parent can still steer without the child becoming a passenger.
Molly
GBG! Milwaukee