caioxavier on "Help with category page"

Hey guys, I'm new to WP and PHP so I can't really rely on my hardcoding skills to get what I want, so I need your help. It should be simple:

I have category pages and child categories in some of them. I want to display in the category page, links to the current parents and child categories, so the user can filter the posts.

Imagine we are broswing Category 1, with has 2 child categories. All I want is to display:

Category Title

[All] - [Child 1] - [Child 2]

[the loop]

Only the content and category title would be displayed if there are no child categories.

I'm aware I could do this by making specific page templates, but I want to keep everything lean and dynamic, so my client can change the categories as he pleases.

Thank you guys in advance!