Knowing you need to protect your phylactery you decide to turn your mothers corpse into a guardian for it and return the organ back to its home. You pick up your phylactery in your right paw and walk over to your mothers corpse, replacing it into her chest cavity reconnecting the various veins and arteries.

Before sealing the wounds up on the chest and the neck, leaving the body back in her former pristine self. You then follow the instructions within the tome and raise your mother into undeath binding her soul to you, setting her as the guardian of your phylactery...