POLL: What is your preferred location for ViewModel Hydration?

I've been torn on this topic, as I see value either way. Now that I'm working on a ViewModel-First navigation library, I'm trying to decide where a user will typically (in a well-factored code base) hydrate their ViewModel.

by hydration, I'm not only referring to setting initial properties, but also calling async services and retrieving VM data.

OPTION 1: Hydrate in the page

    public partial class FirstPage
    {
        FirstPageViewModel _viewModel;
        IFooService _fooService;
        public FirstPage(FirstPageViewModel viewModel, IFooService fooService)
        {
            _viewModel = viewModel;
            _fooService = fooService;
            InitializeComponent();
            BindingContext = _viewModel;
        }

        protected override async void OnAppearing()
        {
            base.OnAppearing();
            _viewModel.Person = await _fooService.GetTheCoolestPersonAsync();
            // more long running tasks.
        }
    }

    public class FirstPageViewModel
    {
        public Person Person {get;set;} // too lazy to write a bindable person.
    }

OPTION 2: Hydrate in the ViewModel

    public partial class FirstPage
    {
        FirstPageViewModel _viewModel;
        public FirstPage(FirstPageViewModel viewModel)
        {
            InitializeComponent();
            BindingContext = _viewModel;
        }

        protected override async void OnAppearing()
        {
            base.OnAppearing();
            await  _viewModel.Init();
        }
    }

    public class FirstPageViewModel
    {
        IFooService _fooService;
        public FirstPageViewModel(IFooService fooService)
        {
            _fooService = fooService;
        }

        public async Task Init()
        {
            Person = await _fooService.GetTheCoolestPersonAsync();
            // more long running tasks.
        }

        public Person Person {get;set;}  // too lazy to write a bindable person.
    }

OPTION 3: ?????????

For your preferred direction, what is your rational for leaning that way?