Meanwhile, Papa Moose and Mama Squirrel were up and down two flights of stairs with water, poultices, salves, and teas. A couple of the herbs in the tea seemed to be a little help, and of course the water helped keep the fever down. But Alvin knew that even with the ones that had a rash, the salves and poultices did no good at all.

Of course he and Arthur Stuart helped-chasing up and down stairs with things so Papa Moose didn't have to, running errands in town, keeping food in the house, tending the fire, hauling the chamber pots to and from the sickroom. Moose and Squirrel didn't allow them to come inside, though, for fear of contagion.

That didn't stop Alvin from spending most of his concentration on the sick children. Having seen the disease at the end of its course in Dead Mary's mother, he knew what to look for, and kept repairing the damage the disease was doing, including keeping the fever down enough that it didn't harm them.

He also studied the sick children, trying to find out what caused the disease. He could see the tiny disease-fighting creatures in their blood, but he couldn't see what they were hunting down the way he could with gangrene or some other sicknesses. So he couldn't find any way to help them get rid of the cause of the disease. Still, he could see that it helped to keep the fever down and the seepage of blood under control. With Alvin tending to their bodies, the disease ran its course, but quickly, and never became dangerous.

And in the healthy children, whom he examined one by one, he found that most of them were already producing the disease-fighters, and he took such preventive action as he could.

What interested him, though, was the handful of children who did not get sick. Were they stronger? Luckier? What did they have in common?

Over the days of sickness in the house, Alvin checked on each of the ones who wasn't ill.