There are multiple event sessions...There are 3 sessions a month
Not sure what is the difference between an event, event session and a session, or if they'reN) the same thing. I'm guessing a session is a many part of a single event. If that's the case, and Event1 can have 3 sessions, you should have a tblClients, tblSession and tblEvents. The event id would appear in the session table for each session related to the event. The client id would appear in the session table for each client related to the session, along with their registration status (Y/N). Not sure I see the need for a registration status table.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.