  We consider a class of continuous phase coexistence models in three spatial
dimensions. The fluctuations are driven by symmetric stationary random fields
with sufficient integrability and mixing conditions, but not necessarily
Gaussian. We show that, in the weakly nonlinear regime, if the external
potential is a symmetric polynomial and a certain average of it exhibits
pitchfork bifurcation, then these models all rescale to $\Phi^4_3$ near their
critical point.
