Laravel 5.5 multiple controller on single view

I have web pages that have search form that need to populate data from database like category, there lot of page on my site like gallery blog etc.

every page has the same search form.

so I decide to use @section and @extend for main content and keep the search form on my main layout.

here my controller

public function index()
{
    $post = Post::all();

    $categories = Category::all();

    return view('events.show', compact('post', 'category'));
}

public function show($slug)
{
    $post = Post::where('slug',$slug)->first();

    $categories = Category::all();

    return view('events.show', compact('post', 'category'));
}

on my code above I need to call category list like every function also every controller

there's a way to make it without $categories = Category::all(); every function also every controller ?...

so just call once and work every page.

via Chebli Mohamed