  The gravitational influence of a second satellite on the rotation of an
oblate moon is numerically examined. A simplified model, assuming the axis of
rotation perpendicular to the (Keplerian) orbit plane, is derived. The
differences between the two models, i.e. in the absence and presence of the
second satellite, are investigated via bifurcation diagrams and by evolving
compact sets of initial conditions in the phase space. It turns out that the
presence of another satellite causes some trajectories, that were regular in
its absence, to become chaotic. Moreover, the highly structured picture
revealed by the bifurcation diagrams in dependence on the eccentricity of the
oblate body's orbit is destroyed when the gravitational influence is included,
and the periodicities and critical curves are destroyed as well. For
demonstrative purposes, focus is laid on parameters of the
Saturn-Titan-Hyperion system, and on oblate satellites on low-eccentric orbits,
i.e. $e\approx 0.005$.
