  The stellar spin orientation relative to the orbital planes of multiplanet
systems are becoming accessible to observations. For example, 55 Cancri is a
system composed of 5 planets orbiting a member of a stellar binary for which a
projected obliquity of 72+-12 deg relative to the orbit of the innermost planet
has been reported (Bourrier & Hebrard 2014). This large obliquity has been
attributed to the perturbation induced by the binary. Here we describe the
secular evolution of similar systems and we discuss the case of the 55 Cancri
system more deeply. We provide two different orbital configurations compatible
with the currently available observations.
