Heads or tails

So I am at a loss. Alena just loves Maxie and is always wanting to pet her. But which end do I put her little fingers at? If I let her reach for the face she tugs on the ears, pokes the eyes and is oh so close to her mouth. I could never see Maxie nipping at Alena but she is an animal and it could happen. So do I put her little probing fingers at the tail end? She just loves rubbing Max and smacks her back but she also goes for the tail. She hasn't yet pulled on the tail but her little fingers have gotten oh so close to her icky butt! So what do you think... head or tail?