Ian Parkin is the author of this post.
What is a familiar spirit? A familiar spirit is a spiritual guide, usually in animal form. With a pet as a familiar spirit guide you may find it possible to communicate telepathically and become well acquainted with its mystical help and wisdom.
If you are an individual of even remotely heightened (psychic or emotional) sensitivity, you will already know that feeling a deep personal connection with an animal (be it a pet, or otherwise) is not particularly uncommon.
This may come in many forms, from establishing an immediate bond with a puppy you found on the street, simply "knowing" that the cat you are to foster is just right for you, or even having an odd "Disney princess" sort of moment where a wild animal approaches you in a perfectly friendly manner, as if it had known you for years.
Sometimes, these connections appear as natural and as complete as those you can form with other human beings. The lines of communication can feel fully open, even despite us belonging to different species. It is quite possible that some of the interaction does occur via the subconscious and that our cross-species rapport happens on more than one level.
Pets saving lives or warning their human friends of impending danger are but one facet of this mutually beneficial bond. Such relationships needn't be ignored and should be cherished for they bring us closer to nature and to the universe as a whole.
This is however not the only way a significant animal, or a familiar spirit, if you will, may appear in your life.
When people initially embark on astral projection, they will usually first wander around the physical plane, trying to determine whether what they're doing is "for real" or a mere illusion. Once they become more comfortable in their new astral shoes, they will gradually shift to higher planes and begin exploring the scenery beyond.
This is where the other type of familiar spirit guides usually appears. Since the astral plane is such a vast space (if we can call it that, for it is very much beyond the limitations of both space and time), and so different from our own reality, in the beginning the traveller is provided with a guide which, more often than not, comes in animal form. The said animal, often of an exotic kind, easily communicates with the traveller, giving them invaluable advice and directions. If treated with respect, it can share a lot of wisdom and make one's journey through the astral plane pleasant and enlightening.
The look of such a familiar and its character is very often based on (or rather complementary to) the personality of the traveller. The animal's purpose is deeply connected to what the seeking person needs to learn in life in order to progress on their spiritual path. This is why these familiars are so important and can be beneficial to us both in "real" life and on our journeys to the planes above.
Wiki - Familiar Spirits