  The set of canonical decompositions of a cusped hyperbolic 3-manifold is a
complete topological invariant. However, there are only a handful of infinite
families for which canonical decompositions are known. In this paper, we find
canonical triangulations for Dehn fillings of the Borromean rings link
complement and two related manifolds obtained by half-twists. The underlying
triangulations were shown to be geometric by Ham and Purcell. To obtain
canonical triangulations, we show a local convexity result at every face of the
geometric triangulation.
