ISO 26262 is a functional safety standard that targets the automotive domain. This standard focuses on single system certification 1 and does not contain guidelines to certify product lines. Thus, to be ISO 26262-compliant, for each product of a product line, a company must provide almost from scratch all the work products required by the standard, including a safety case. Current product lines engineering methods represent an effective solution to systematize reuse. These methods, however, are not aligned with safety standards and thus they lose their strength when adopted to engineer safety-critical product lines. To enable and accelerate systematic reuse, we introduce VROOM & cC, a new method that by integrating traceable management of commonalities and variabilities at each step of the first two phases of the ISO 26262 safety life-cycle as well as at each stage of the safety case life-cycle permits safety managers to argue about functional safety of product line members by reusing argumentation fragments. To illustrate our approach, we consider a small-sized safety-critical product line.