Bob Brown, the longtime CEO of Guardian Industries, a provider of home security systems, announces that he is taking six-week vacation and that, while he is gone, he will not be reachable. He explains that he wants to “retool and refresh” and that to do this, he intends to get away from the stresses of the job. Brown designates the company’s COO to act as interim CEO in his absence. Brown has never before behaved this way. You are an independent director and chair of the nominating and governance committee at Guardian Industries. The day after Brown’s announcement, as you are considering what steps to take in response, you receive a call from Brown’s executive assistant. Asking for confidentiality, the assistant tells you that he saw some paperwork on Brown’s desk referring to procedures for voluntary admission to a well-known drug and alcohol rehabilitation facility. You have not personally observed any indication that Brown might have a problem with substance abuse. What should you do?