YOU DON’T NEED TO FEEL SORRY FOR HER,” I said briskly. We’d departed the food court, leaving behind the queasy scent of deep-fried foods as we headed down the escalator and out of the Prudential Center. “My sister isn’t like you and me. She doesn’t bond, feel empathy or receive comfort from other human beings the way you and I would. Just because she’s alone doesn’t mean she’s lonely. Technically speaking, she would feel the same standing in a crowded room, or even in the arms of a man who claimed he loved her. It’s part of her personality disorder.”

“Meaning solitary confinement is hardly punishment for someone like her?” D.D. asked.

“Yes and no. It’s not the company of people she misses; it’s the stimulation. Shana may not feel lonely in her cell, but she does grow bored.”

“Not bored enough to change her ways,” Phil stated.

“The kind of change required is too deep-rooted. Bonding disorders are very challenging. Best odds of success are when the subject is younger than five. Given that Shana has spent her entire adolescence and now adult life behind bars . . .”

“She really stirred blood into her applesauce?” D.D. asked.

“Shock value,” I informed her. “Superintendent McKinnon had assigned Shana a new caseworker, which, given Shana’s limited social life, was basically the equivalent of handing her fresh meat. Shana told the man she was a servant of the devil, and mixing blood into applesauce revealed patterns that helped her foretell the future. For example, the caseworker would be dead by the end of the month. Then, when he had a heart attack just three weeks later . . .”

“No way!” D.D. stopped walking.

“Not a heart attack,” I assured her. “But a panic attack. Most likely brought on by spending three hours a week in the company of my sister. Needless to say, the caseworker retired. And my sister went back to plotting new ways to entertain herself.”

“Like contacting a killer?” Phil asked.

I didn’t know what to say anymore. I felt suddenly exhausted, worn-out. The things I understood professionally about my sister, versus the things I wanted to feel about her personally.

Such as, just because I couldn’t feel pain didn’t mean my family couldn’t hurt me.

She dreamed of me, whispered my name. My big sister. We’d spent only a few years together, one with our parents, two in various foster homes. And yet our lives seemed forever intertwined.

“Have you ever played the bar game?” I asked now.

Both detectives had stopped walking. We were outside the Prudential Center, standing in the middle of a bustling sidewalk, streams of humanity splitting around us. Midday in downtown Boston. Commuters, tourists, residents, all going about their very important business. While we discussed murder, with the late fall air sharp against our cheeks and the sun already contemplating its decline.