Can my stepdad remove my mom from life support without my say?

On Thanksgiving day my mom was hospitalized and put on life support. There is no living will for us to go by. My stepdad wants her life support removed, we her 3 children, 2 brothers, and her mother do not want this at this point. Can he do this without our concent? We need answers now please. We live in Georgia, so we need to know Georgia's law on this.