There were several things of note in what she said, the first being that he said 'probably not' as if he did not know. The second was the tone that he used when he talked about them. Not sad, more like resigned, or like it was a subject and thought he had chewed on until it was bitter and lost it's flavour.
Granted, she had heard people be glad that their parents were gone before, but it was usually stated with a bitter anger, not at all the way Bucky talked about his family. Even thoughts he dealt with people who lost loved ones on an almost daily basis, there was no correct way to react, for her or to the person across from the desk, no matter what any book tried to say.
Setting her tea down for a moment so she could flex her fingers, still from holding it, "Why? Do you think they wouldn't like you the way you are?" Rejection was everyone's fear, man, woman, adult, child, no one was safe from it. Rejection, and a fear of being left alone because of it. There was a chance she was wrong, this boy already seemed to be different than what she expected.