My elderly father had allowed an employee to stay in his carport apartment free of charge with no written agreement. She has since started a relationship with his son and no longer lives in the apartment. She will not give up the key to the lock and is the only one with the key to the apartment. I wish to now issue her a notice to vacate. If need me possible eviction notice. How do I go about it and do I have the law on my side simply because I wish to have my apartment returned to me along with the key to gain access once again?

1. First whose apartment is it. Yours or your elderly father?

If the home and apartment belongs to the father, there is nothing you can do, except what he wants.

Who has a key has no bearing, the legal owner of the property can give a notice for them to move, if they do not move, you go to court and get a legal eviction though the court.

Your elderly fathers son? Is that your brother?

1. First whose apartment is it. Yours or your elderly father?

If the home and apartment belongs to the father, there is nothing you can do, except what he wants.

Who has a key has no bearing, the legal owner of the property can give a notice for them to move, if they do not move, you go to court and get a legal eviction though the court.

Your elderly fathers son? Is that your brother?

The home and apartment belongs to my father.
The brother is my brother
The father wants the lady to leave. She has no written agreement to stay month to month and pays no rent. She started out being given three months to stay in turn she provided services as a care giver to my father.

She has since started a relationship with my older brother and lives in his home. Her belongings are still in the apartment and she and the brother are controlling the key.

Since my father agrees that she needs to be told to leave I have since served her with a five day notice to vacate as per Louisiana code to tenants.

My next step if she does not leave is to seek a court judgement for her to be told to vacate.

Where did you see a 5 day notice? I see LA law requires a 10 day notice for a month to month tenant unless rent is unpaid. And since she was allowed to live there free of charge, that isn't the situation.

Otherwise, you are doing this correctly. As long as she has belongings there you can't take possession. However, you CAN (or rather your father can) hire a locksmith to change the lock but you must give her a key. Since you have started the eviction process, I would wait until you get an eviction order from the court.