Jay's first lie on then stand is awfully telling

In the second trial Jay takes the stand. After stating his name and address, he's asked about his living situation. He states that he lives with his mother. When asked if any other relatives live with them he says no. He testifies that this has been the case for about 6 years. What happened to worrying about his grandmother? What about the uncle? Why lie about something that is so clearly untrue? He's afraid of someone alright, but it isn't Adnan.