So dd2 is quite verbal (I think) we are waiting for SALT assessment. But doesn't talk much. She is nearly 6 and I can honestly say I have never had what you would call a conversation with her 
She doesn't like any kind of question or anyone to tell her things. If I do ask an open question I will get one of three responses:
A) "I don't know" - this one all the time to any question (what did you do today at school?/what would you like as a snack?/ what do you like about stampy cat/ Dan TDM videos? Why do we own over 100 skylanders? And pretty much every question ranging from very simple to more complex)
B) stony silence
C) "I do not want to talk about this!"
She is a bit better with closed questions but often answers yes then thinks and says no or vice versa.
Most of the time I don't think she even heard the question (even when I say her name and make sure she is focused on me) or maybe picks up on a couple of key words but I don't know.
I'm finding it really hard to understand how to get through the barrier to find out what - at a basic level - makes her happy. And she won't talk about anything personal to her. I only found out about some bullying (which was sorted quickly by school) when her sister found her in tears and she told her a few words so DD1 could guess what was happening and tell the teachers/us. I don't think I am expressing this well and think it sounds like I am prying into her thoughts but I really get nothing from her and think she would tell me if she knew how.
Has anyone else had this? Is it common? Have you managed to connect with your dc? Feeling very out of my depth and a bit sad.