Two years ago a groomer killed my dog then lied and said he had a heart attack but, when a tv reporter confront her with Sparky's Necropsy she confessed to her lie. Sparky's cause of death was suffocation with red marks around his neck. Last year I filed an unlimited Civil Lawsuit in the Superior Court a year ago, representing myself. The defendant also was representing herself until last week when I got a notice from the lawyer she has hired plus a stack of questions (interrogatory), most are personal questions such as, list of every school I have attended or how much money I was making at the time of the incident? Since I am the Plaintiff, do I need to answer these type of questions? To me, these type of questions, are not relevant to my case.
You more or less do have to answer. The details depend on your state's rules of civil procedure: the Washington rule is here. You can object, and the court could agree with you, or can agree with them and then you would be ordered to answer the questions. In California, you can ask 35 questions, in Ohio it's 40 (or more if the court allows).