On the drive to the house, I pick up my mobile. “I need to call my friend Liz,” I say, half to myself and half to Minal in the backseat.

Always ready, she chimes in: “Liz who?”

“I only have one friend named Liz,” I respond.

“You used to have two.”

“Yes.”

But your other friend Liz died, right?”

“Yes,” I say. “So I can’t call her.”

“You could always call her in your mind?”

I put my phone down and concentrate on driving. “Yes, I could always call her in my mind.”