Laravel 5 getparentsTree

Trying to get property 'title' of non-object (View: C:\php\laravellp\resources\views\admin\product_edit.blade.php)

C:\php\laravellp\app\Http\Controllers\Admin\CategoryController inner title line error i think

public static function getParentsTree($category,$title)

{

    if ($category->parent_id == 0)

    {

        return $title;

    }

    $parent = Category::find($category->parent_id);

    ***$title = $parent->title. ' > ' . $title;***


    return CategoryController::getParentsTree($parent,$title);

}

via Chebli Mohamed