sort of

{!! Form::select('category_id', listSelect(App\Category::all()), null, array('class' => 'form-control','multiple' => TRUE)) !!}

// add to /app/helpers.php
function listSelect($categories){
    $cats = $parents = array();
    $cats['-1']= 'Select Category';

    foreach ($categories as $category) {
        if ($category->parent_id == 0) {
            $parents[$category->id] = $category->name;
            $cats[$category->name]=array();
        }
    }
    foreach ($categories as $category) {
        if($category->parent_id > 0) {
            $parent_name = $parents[$category->parent_id];
            $cats[$parent_name][$category->id]=$category->name;
        }
    }
    return $cats;
}