Magic Forums

I've been reading around about familiars and what some of you have said, is that the familiar "chooses" the person. Could that mean that my cat Sable could be my familiar? My mother said when she brought Sable home when I was about five that the cat just walked up to me and basically has never left my side. I never go anywhere in the house without her basically. (she is not allowed outside since their are many dogs and since she is black and the superstitious people out there) I can't go to bed without her even though she ditches me later on but always comes back. So does that mean she has the possbility of being my familiar or spirit guide?