Redirect with session from FormRequest Laravel

I was using validator inside controller and it can sent messages through session.

return redirect()->back()
            ->withErrors($validator)
            ->with([
                'editModal' => 'editModal',
                'msg'       => $msg
            ]);

Then, I tried using FormRequest in Laravel. This FormRequest works, but I want to send some data with session if validation is failed. But I can not find the good way, I just can send it using

$validator->errors()->add

Is there a way to send a message through session like with() in controller?

via Chebli Mohamed