  In this proceedings we consider several states, namely the $D^*_{s0}(2317)$,
$D_{s1}(2460)$, $D^*_{0}(2300)$ and $D_{1}(2430)$, which appear to defy
description as simple quark-antiquark pairs. Theoretical input from unitarized
chiral perturbation theory suggests they can be understood as emerging from
Goldstone-Boson--$D$-meson scattering.
  We present results from an $SU(3)$ flavor-symmetric lattice QCD simulation at
large pion masses suggesting that there exists a $\pi D$ bound state in the
flavor-sextet representation that cannot emerge for quark-antiquark states, but
that appears naturally from the multiquark states. Moreover, we find repulsion
in the [15] representation, which establishes the pattern predicted for the
interactions of Goldstone bosons with $D$ mesons. This suggests these states
may have the structure of hadronic molecules.
