Beginner: page "date" defined by casual user

Hello, I'm new to grav and thinking about using it as the basis for my sister's website. She would regularly create (sub) pages representing events/dates, not necessarily in the order in which they occur. I want those to be presented in a sorted manner, not by creation time but by the date/value she specifies in the content.

She's not a technically minded person, so while writing Markdown using the Administration Panel shouldn't be an issue, I cannot expect her to fiddle with secondary config/meta files. What would be the best way to go about this?

I just stumbled upon the page "frontmatter" in the documentation, don't know how I missed that. From what I understand, my sister could begin her pages specifying a date field, and then just type the regular markdown content below. If the creation of new sub-pages is trivial from the admin panel, then I think I can take care of the rest just fine.