Friend scope in C++

Question

If I have three classes, A, B, C. A and B are friends (bidirectionally). Also, B and C are friends (bidirectionally). A has a pointer to B and B has a pointer to C. Why can\

Answer 1

This is all well summed-up here:

What does it mean that "friendship isn't inherited, transitive, or reciprocal"?

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It means that classes derived from a friend class don't automatically become friends (do you trust the kids of your friends?), a friend of a friend doesn't automatically become a friend (do you trust the friends of your friends?), and that a class declaring another class as "friend" doesn't automatically become a friend of that class (do you trust anyone who calls you a friend?).

from

http://yosefk.com/c++fqa/friend.html#fqa-14.4