In this photo created with an in-camera multiple exposure, Registered nurse Cathy Cullen, part of the first group of nurses who had been treating coronavirus patients in the hospital’s intensive care unit, poses for an in-camera multiple exposure in the empty COVID-19 ICU at Providence Mission Hospital in Mission Viejo, Calif., April 6, 2021. Cullen sometimes tears up when thinking about what she and the other nurses endured. “The birth of my children and marriage aside, being a part of this team, this endeavor, and this pandemic is by far the greatest, worst, most rewarding, most painful thing I have ever done in my life,” she says. (AP Photo/Jae C. Hong)