LiveData Observer not Called

To get same reference of ViewModel of your Activity you need to pass the same Activity instance, you should use ViewModelProviders.of(getActivity). When you pass this as argument, you receive instance of ViewModel that associates with your Fragment.

There are two overloaded methods:

ViewModelProvider.of(Fragment fragment)

ViewModelProvider.of(FragmentActivity activity)

For more info Share data between fragments

I put this code inside the onActivityCreated fragment, don't underestimate getActivity ;)

if (activity != null) {            
     globalViewModel = ViewModelProvider(activity!!).get(GlobalViewModel::class.java)
    }


globalViewModel.onStop.observe(viewLifecycleOwner, Observer { status ->
            Log.d("Parent Viewmodel", status.toString())
        })

This code helps me to listening Parent ViewModel changes in fragment.