  Ultra-short period (USP) planets are exoplanets which have orbital periods of
less than one day and are unique because they orbit inside the nominal magnetic
truncation gap of their host stars. In some cases, USP planets have also been
observed to exhibit unique dynamical parameters such as significant
misalignments in inclination angle with respect to nearby planets. In this
paper, we explore how the geometry of a multi-planet system hosting a USP
planet can be expected to evolve as a star ages. In particular, we explore the
relationship between the mutual inclination of the USP planet and the
quadrupole moment ($J_2$) of the host star. We use secular perturbation theory
to predict the past evolution of the example TOI-125 system, and then confirm
the validity of our results using long-term N-body simulations. Through
investigating how the misalignment between the candidate USP planet and the
three other short-period planets in the TOI-125 system arose, we intend to
derive a better understanding of the population of systems with misaligned USP
planets and how their observed parameters can be explained in the context of
their dynamical histories.
