The day after Thanksgiving, my stepfather and brother and husband—a/k/a Grandpa and Uncle Rudy and Daddy—took Martin to see The Good Dinosaur. Martin, who had seen the movie promoted on Disney Channel and been asking to go, came home all smiles from the theatre.

“Hi, Martin!” I greeted him. “How was the movie?”

“It was good!” he said.

“Did you enjoy yourself?”

“Yes.”

“What was your favorite part of the movie?” I asked.

Martin didn’t hesitate. “My favorite part was when the dinosaur boy’s dad died,” he said, laughing.

“When his dad died? Wasn’t that very sad?”

“Yes!” Martin said, still laughing. “It was sad!”

Confronted with what must have been a tear-jerking scene for the other movie patrons, Martin seemed unable to suppress his glee.

Last month I lost a friend. We weren’t close; we’d known each other in junior high school, and reconnected a few years ago via Facebook, and discovered that we shared interests in fitness, real food, and faith. By the time we reconnected, Jenny was already fighting her second bout with breast cancer. I knew that she was in and out of chemotherapy and making frequent doctor visits. Yet, to me, her cancer never seemed present or imminent, because I never saw her in person and because her Facebook posts were always upbeat.

One night, just before I went to bed (alone; Adrian was away on business), I checked Facebook and saw that another user had just tagged Jenny in a post something like, “Pray for Jenny. She’s gone into the hospital and isn’t doing well.” I prayed for Jenny that night. I didn’t worry too much. She’d been in the hospital before and gone home quickly. Besides, her status updates that week had been banal: She loved her new juicer. She was considering seeing a doctor a few towns away and wondered whether anyone would like to share the ride. Everyday stuff.

Jenny must have been on my mind overnight, because when I woke around 5:30 a.m. I checked Facebook again immediately. During the early morning hours, a different user had posted, on Jenny’s wall, something like, “Jenny’s been taken off the ventilator. Her husband asks for prayers that she passes in peace and they can grieve.”

Only days earlier, on-line, Jenny had seemed vibrant and untroubled. I decided that “taken off the ventilator” must mean that the doctors wanted to give her the chance to pull through on her own, and she would.

At 7:15 a.m., Jenny’s aunt posted something like, “R.I.P. my beautiful niece. You fought hard.” By that time, Martin was seated at the table eating breakfast, so I set down my iPhone, left the kitchen, and started to speak with Jenny, in case she could listen. I’m glad we found each other through Facebook, and I’m sorry I didn’t realize how advanced your cancer was. I wish I’d realized. I would have said more to you. I would have talked about sleeping over at your house in seventh grade, and some of the crazy afternoons we had in your family’s swimming pool. Remember?

When I returned to the kitchen to finish giving Martin his supplements, I was crying. He noticed (that’s encouraging) and asked me why.

“I just lost a friend. My friend died. My friend died, and it’s making me very, very sad that I won’t see her again, or talk to her.”

“Oh,” Martin said. Then he smiled, giggled, and said, “Your friend died!”

“That’s not a funny thing. It’s something that’s making me sad.”

Martin said, “Okay,” and kept giggling.

It was, fair to say, one of our more—ahem—challenging moments. I stood in the kitchen, still crying, and my son had no response other than to laugh at my grief.

Here’s one whopper of a reason I stick with biomed, with trying to heal Martin from the inside out: You can teach a lot of things. You can teach eye contact. You can teach small talk and germane responses. You can even teach how to mimic emotion. But you can’t teach empathy.

At least not any way that I know how.