Yes, his sister can serve him. After she does, have her fill out a proof of service setting forth when, where, and what time she served him. The form can be found here: http://www.courts.ca.gov/documents/fl115.pdf Good luck.
You cannot simply add fiance's name to the birth certificate and think that it fixes the problem. Bio-dad has legal rights (and obligations), and if you want fiance to be the "legal" dad, then he has go through the adoption process. I am including links below that may be of some help. Good luck.
She wants to move with the kids mid-school year? Yikes. I'm sure you've already heard this but...you really need to hire an experienced family law attorney to assist you. :)
If you do not have a pending case, then you need to file one immediately (which will prevent the other parent from removing the children from the state of California without written consent or a court order). You then need to file a Request for Order seeking custody and visitation orders. This will do 2 things:...
You need to thoroughly document all of the missed phone/web chats and then file a Request for Orders to modify the custody and visitation orders. Alternatively, you can file a Contempt Action against him. I am including links below which will explain how to do that. Good luck.
I agree with my colleagues. If you do choose to include a Memorandum of Points and Authorities, you can either attach it to your Responsive Declaration or file it separately (so long as it has an appropriate caption page).
Unless you are a lawyer, I would caution against drafting your own Memorandum of Points and Authorities, especially since the judge will question whether you are citing to good law. If you responding to the cases cited by the opposing counsel, then make sure you...
You may need to get a domestic violence restraining order if you fear for your safety. With regard to renting rooms, I doubt the state can do anything more than investigate you for welfare fraud. I would suggest consulting with an attorney to advise you of your rights. And I'd also suggest not admitting to welfare fraud on this public forum.