  We present a mirror model moving in the quantum vacuum of a massive scalar
field and study its motion under infinitely fluctuating quantum vacuum stress.
The model is similar to the one in \cite{PhysRevD.89.085009}, but this time
there is no divergent effective mass to weaken the effect of divergent vacuum
energy density. We show that this kind of weakening is not necessary. The
vacuum friction and strong anti-correlation property of the quantum vacuum are
enough to confine the mirror's position fluctuations.
