I'm surprised the SW is asking you to ask your dd the questions and not talking to her herself. When we adopted dd3 birth sister of our other two, our SW had a session with all of us together, we had to play games etc with the girls, it was all recorded ( dreadful ) Sorry, can't help you with what to ask your dd. may be worth talking to the SW to find out more.
Our social worker has asked me to ask my DD (aged 8) some questions and to record her answers (in relation to the home study we are doing - stuff about how she feels about the new child coming to join our family).
I must admit feel quite stumped! Anyone else had to do this and care to share what you asked, please?