The organization recently ran a vaccine clinic in the heavily Polish and Latino communities, where some have hesitated to get their children vaccinated. MariCarmen Zavala brought her 8-year-old son, Louis Perez.

“It’s really important for me to get the vaccine for him so that my son is able to do the activities that he likes to do,” she said. “My two sisters-in-law don’t want to vaccinate their children based on the misinformation they hear. So he will help protect the ones who are not.”

In Ely, Minn., two of Michelle Greener’s children, Sophie, 10 and Liv, 11, share a rare disease — Ehlers-Danlos syndrome — with her husband, and she has a 16-year-old she adopted when the girl’s mother, the family babysitter, died in 2019. That child, Emma, is severely disabled and at very high risk for complications from Covid.

Ms. Greener, 38, takes care of all three while her husband goes to his manufacturing job. First she was vaccinated, and the outside world belonged largely to her alone. Then, a shot for her husband: another worry down. Next came Emma, who had emergency surgery during the pandemic. Ms. Greener stayed with her in the Twin Cities, and limited contact with her younger children, who at the time were too young to be vaccinated.

“The day they approved the vaccine for 12 and up is the very day I drove two hours down to Duluth,” said Ms. Greener, whose house is so distant that she spends nights staring at the northern lights. “I cried all the way in and cried all the way out.” One child had reacted poorly to another vaccine in the past.

“That was very emotional, a little stressful not knowing how my younger daughter would handle it,” Ms. Greener said of Liv. “I eat and breathe medical, that’s all I’ve done — all I think about is how I am going to keep these kids alive. Now we have done everything we can do to keep Emma alive. At this point, I am just dependent on the rest of the world.”