You have to file a lawsuit to evict them. A lot of people handle their own evictions but many of them are landlords who have been through th mill before. Since it sounds like this is your first time, you might do everything "right", but if the notice was improper or improperly delivered or filled out...., or you haven't waited the requisite amount of time to sue, or your pleadings are defective......you may be back at step one before you know it, with angrier non-paying "tenants" still in occupancy.....
The response given is not intended to create, nor does it create an ongoing duty to respond to questions. The response does not form an attorney-client relationship, nor is it intended to be anything other than the educated opinion of the author. It should not be relied upon as legal advice. The response given is based upon the limited facts provided by the person asking the question. To the extent additional or different facts exist, the response might possibly change. Attorney is currently licensed to practice law actively only in the State of Illinois, inactively in Florida. Responses are based solely on Illinois law unless stated otherwise.
You will have to file a lawsuit to evict the tenant.
You may use a lawyer. Many landlords do. You may proceed on your own. This might elogngate the process, but perhaps not.
You have to evict them. Don't try it yourself, hire an attorney.
Because these are your parents, you may want to think about giving them some cash to leave by a certain date.