He was interested in it and how it worked, and he even bought several medical books so he could understand it better. He knew that if he could understand it, he could better take care of her.

One morning when she went to take her bath, they realized that the hot water was out. My father got up at 5 a.m. and boiled pot after pot of hot water for her bath because he knew that she wouldn’t be able to tolerate the cold.

Now my father is taking care of my grandmother, his mother. I know the rule of thumb is that there is a “dutiful daughter” who takes care of the parent, but my daddy is the “dutiful son.”

He calls me often to ask me questions about my grandmother’s condition, asking me about her INR, her aortic valve, and how Lasix works. He bought a pocket pulse oximeter to keep track of that, too. He weighs her every day and adjusts her Lasix and other diuretics accordingly. I’m totally impressed.

About a week ago, my grandmother was hospitalized for a CHF exacerbation. He had been concerned for several days, as she was gaining some weight and having

dyspnea even going to her bedside commode. So off to her PCP (yes, people still do that, apparently) to see what was up.

Dad said, “I told the doctor that I thought she was in CHF. After he listed to her lungs, he looked at me and said, ‘I think you’re right.’ ”

Before I came to town, he asked me to bring my stethoscope so he could learn how to listen to my grandmother’s lungs. After this bout of CHF, Dad said he wanted to know what to listen for so he’d know sooner if she was in trouble.

As I gave him a brief lesson, he was an attentive student. “I can hear the crackling sound here, but not here,” he said. “That’s right,” I told him.

“The higher you go, the less you hear because the fluid builds up mostly based on gravity.” He nodded his understanding. “Ah hah,” he said.

I don’t meet many people like my father in my work. I’m always amazed at some patients’ family members who really do know the ins and outs of their loved one’s illness.

They are rare specimens in the world. Most of the people we see think knowing their medicines means being able to tell us what color their pills are. And they usually don’t even know that.