How do I set Z-order for VBox in JavaFX?
With the toFront() and toBack() functions you can indeed influence the z-order, but be aware that this also influences the layout. The HBox and VBox for instance also use the sequence of children to do the layout and moving something to the front will also move it to the end of the [HV]Box. This might not be what you are looking for.
I was looking for a way to do an animation with the animated Node on top of all others, without messing up the layout. There seems to be no way to do that because the z-order and layout order are both taken from the child-order.