Are the stars always in the same position relative to earth?

[obelix]

depends on the time-scale you are talking about ... stars are pretty much in fixed position w.r.t. both rotation and revolution of the earth (they do move, but being far far away, their movement makes hardly any change in the arc-length with respect to our coordinate system), but if you are think of visible sky, then it changes with months ... simply because during the earth's revolution around the sun different parts of the sky are visible to us.