  We study the dynamics of a star orbiting a merging black-hole binary (BHB) in
a coplanar triple configuration. During the BHB's orbital decay, the system can
be driven across the apsidal precession resonance, where the apsidal precession
rate of the stellar orbit matches that of the inner BHB. As a result, the
system gets captured into a state of resonance advection until the merger of
the BHB, leading to an extreme eccentricity growth of the stellar orbit. This
resonance advection occurs when the inner binary has a non-zero eccentricity
and unequal masses. The resonant driving of the stellar eccentricity can
significantly alter the hardening rate of the inner BHB, and produce
observational signatures to uncover the presence of nearby merging or merged
BHBs.
