What is the secret Reddington keeping from Elizabeth? Does Elizabeth know Reddington is her mother?

The Blacklist season 6 revealed that  Raymond Reddington is Elizabeth Keen’s father but the man she knows is not the real Reddington.

In season eight, Raymond Reddington revealed to Elizabeth Keen that he was actually N-13, a spy Elizabeth Keen had been looking at the FBI. Elizabeth Keen learnt that her biological mother was actually a spy called Katarina.

“The Blacklist” follows Elizabeth Keen, a rookie FBI special agent and criminal profiler who has her entire life uprooted as Raymond Reddington insists on speaking only to her. Raymond Reddington was a master criminal who vanished a long time ago and came back as the concierge of crime.

Elizabeth Keen is picked up by the FBI and driven to a black site to meet Reddington who tells the FBI that he has a list of the most dangerous criminals in the world that he has compiled over his criminal career called the “Blacklist” and offers to help the FBI track down and apprehend them in exchange for immunity from prosecution.