1There are two solutions that i found on the search
2
31. use laravel form select and prepend the null value in starting
4{!! Form::select('parent_id', $category_list->prepend('Select a parent (optional)', ''), $category->parent_id, ['class' => 'form-control']) !!}
5
62. Or use `sometimes` validation
7 'email' => 'sometimes|required|email',
8This will check if the value resides in the the data or column selected