Child page/component replace parent page/component?

I have a child page of let's say parent/. The parent page has a layout as well that adds a sidebar for matching routes.

So I have

/playground.vue
playground/
playground/child.vue

I have it right now so that I can get to playground.vue and playground/child.vue but the playground.vue content is still on the page. I just want to swap the content. Is that possible? I'm probably not explaining well.