Hurtful truths of life

This is a story of a child (a grown-up adult whom I know) and her mother who gave her away when she was barely 1 year old. The child never knew about the truth until one day she found her original birth certificate. She later met up with her biological mother. Read the extract of their dialogue below keeping in mind the fact that they have already known the names of each other after the meeting.

Child calls birth mother on her mobile and this is a small extract of the beginning of their phone dialogue.

Child: "Hello, are you xxxxxx (name) ?"
Mother: "Ya, who are you?"
Child: "I am xxxxxx (name)."
Mother: "Huh? Who is xxxxxx?"
Child: "I.... I am your biological daughter. We met that day."
Mother: *pauses for a while* "Oh... you mean last time one lah..."

Last time daughter, now not anymore? You can never imagine how much hurt these words have done to the child.