Hi Rosie,
A little tip for you. If you look at the message that you are replying to and look at the bottom right hand corner of that message box you will see three 'buttons'. 'Edit' 'Reply' and 'Peek'.
If you click the 'reply' button then members will know which message you are referring to in your post. Also, the member who posted the message that you are replying to will probably receive an email informing them that you have replied to one of their messages.
It makes life a little easier for all involved.
AdminBrian.