>>Thank you for the correction! But I think the "not permanent" word is just the extension of your "will be lost once the parent is destroyed." :)
>
>But I think the "will be lost once the parent is destroyed" is just the extension of the "not permanent" word. :)
>
>Sorry, I am weak in english grammar.

I was mostly talking about the The document pertaining to this - you don't mention what document. This could then raise the questions "what document" and "where is the document".