What forms do I need to kick someone with a child out?

Your question requires an attorney consultation. It is not a simple question that can be answered on this type of forum. There are many factors that would need to be considered and evaluated. Basically, you will need to serve him with a legal notice to leave and then, if he has not left by the end of the notice period, you will need to file an unlawful detainer (eviction) action with the court. Although the process is not overly complicated, I do suggest that you contact an experienced landlord/tenant attorney for a face-to-face consultation and give him/her all of the facts surrounding your situation. He/she would then be in a better position to analyze your case, advise you of your options and, if possible, make sure that the necessary paperwork and documentation is presented so as not to delay the process.

Can't be discreet. Give him a letter (keep a copy), telling him he has 30 days to leave. When he doesn't file an eviction action. Then if he still doesn't leave, the sheriff will come and move him out.