Did you know that friendship can actually help your brain, heart and immune system? Now that more and more Americans are getting vaccinated, people are eager to reunite with friends they might not have seen in a while. Dr. Sanjay Gupta met up with his friend, Michelle Pfeiffer (yes, that Michelle Pfeiffer). And friendship experts Marisa Franco and Rebecca Adams explain how the pandemic has made us reevaluate our relationships.To learn more about how CNN protects listener privacy, visit cnn.com/privacy