What was Westerberg's mother's opinion of Chris? (Ch.7)

From the text:

“There was something fascinating about him,” explains Mrs. Westerberg, seated at the polished walnut table where McCandless dined that night. “Alex struck me as much older than twenty-four. Everything I said, he’d demand to know more about what I meant, about why I thought this way or that. He was hungry to learn about things. Unlike most of us, he was the sort of person who insisted on living out his beliefs. “We talked for hours about books; there aren’t that many people in Carthage who like to talk about books. He went on and on about Mark Twain. Gosh, he was fun to visit with; I didn’t want the night to end. I was greatly looking forward to seeing him again this fall. I can’t get him out of my mind. I keep picturing his face—he sat in the same chair you’re sitting in now. Considering that I only spent a few hours in Alex’s company, it amazes me how much I’m bothered by his death.”