Cannot Read Cookie Values From Within A Frame

This may or may not be a simple question, but I have been able to find
an answer to this issue in all my searches.

In an ASP application, I'm creating a cookie that stores a username
from pageA.asp

I then try to read the cookie from pageB.asp, which is inside a frame
of pageC.asp.

The problem is I can't read it from pageB.asp. Can anyone please help?

NOTE: If I make pageB.asp as a standalone page without being called
from the frame in pageC.asp, THEN I can read the cookie. But this is
not what I want.

If this wasn't clear please do let me know.