FYI, Two-way binding in VueJS isn't about parent-child communication. It's about binding to input fields and other interactive HTML elements:

"You can use the v-model directive to create two-way data bindings on form input and textarea elements. It automatically picks the correct way to update the element based on the input type. Although a bit magical, v-model is essentially syntax sugar for updating data on user input events, plus special care for some edge cases."

So... I think the term "two-way binding" is overloaded here, and paints an improper picture of what VueJS is actually about.