While I was at work, a process server came to my home looking for my wife. We are separated and have been for some time. The children are under the impression she will return, so I just let them think that. We though best to keep the children out of it until we know for certain.. The process server gave my child, 17 yrs old, the paper. He asked if my wife lived here and he said yes. And the process server ask my son his age and he told him. What can I file at the courthouse to inform the court that my wife and I do not live together. She is in another country and that I can not accept service for her.

The process server has already told the court she does. And that the children ( her children says she does) To be honest I am not sure they are going to believe you at this point. But you can try. You will need to notify the court clerk of this, ( may be best to go down to the courthouse in person)

The court may actually believe you are there lying trying to get your wife out of having to appear in court. I hope you have her current address and contact to give them to prove your statements

When you go to the courthouse, examine the court file and see what the return of service says.

Then I would file something you might call "affidavit regarding service of process" reciting that your child mistakenly told the process server that she still lived there, and giving all other relevant details. Send a copy to the attorney for the plaintiff. Then, if the attorney for the plaintiff tries to file for default based upon the process server's return of service, the attorney is going to have to explain the afiidavit. If you do this, I doubt that this service of process will be considered to be good.