Documentation:Mounted ViewModel

You can insert a ViewModel within another viewmodel at any point where the column in the ViewModel is an object and there's no associated viewmodel class.

The result will be the same as if you would repeat all the things from the ViewModel inside a new nesting from the mount-point. The new Nesting will have the same name as the mounted ViewModel.

One limitation on the mounted ViewModel is that you cannot use the vCurrent_Root in the mounted (since it is owned by the outer view and has the value of the outer ViewModel)