They can, depending on the settings you use. You and person A used to be friends. You failed to say hi one day and A got mad and deleted you and blocked you. You and A can't see or talk to each other anymore. You and B are still friends, though A's friend C and you never were. If you post something public then B and C can see it. But if you post something to friends only, then B can see it, A and C can't.
What makes you ask?