How do I update a page on navigation?

[GlacierFox]

Okay so this might be simple but I can't figure it out. I've got a simple tabbed shell app with three pages - News, Catalogue and Settings.

I've got a webview as the sole component in XAML on the News page which simply displays a link to a blog.

How do I refresh that webview every time I open the news page so displays the latest data? (I'm using MVVM by the way).

Thanks.