A central theme in Kähler geometry for decades has been the search for canonical metrics in Kähler classes. This talk aims to explain a method for studying singular canonical metrics in families of singular varieties with a relative pluripotential theory and a variational approach in families. The main focus of the talk will be the singular Kähler-Einstein (KE) metrics on families of Fano varieties. Following a brief review of singular KE metrics and a variational method, I will introduce a notion of convergence of quasi-plurisubharmonic functions in families. Several classical properties will be extended under this framework. Then, I will present an openness result of the existence of KE metrics via an analytic method and how to establish uniform a priori estimates in families. If time permits, we will conclude by exploring the potential development of this method to study singular cscK metrics. This talk is based on joint works with Tat Dat Tô and Antonio Trusiani.