Is is possible for a game to do things you never programmed in?

Is it possible for the my vectors of an entity to change, and change back?

Is it possible for handles and pointers to interfere, and cause the my vector of another entity to change?

I have a game that is glitching up. Zombies are spawning in the place of blown off arms and heads when they should be spawning at special entities with the action. That action is the only thing that creates zombies. The only vector it stores is the my.x, y, and z. The zombie however, stores the handles of it's arms and head, which are turned into pointers every frame, to position it's limbs and animate them as needed.

Is is something I did, or is my game simply "evloving" as the guy in I, Robot put it?