My wife and I have been married for 8 yrs. and it looks like it may be coming to an end. She has two children from a prior relationship that I have raised as my own. We also have one child (5 yrs) together. After splitting with her ex-boyfriend and the father of the two children, she told their natural father that the girl was not his (even though it was) and after leaving, changed her son's name and had a false Social Security Card made up to prevent him from finding them. She also gave the State a false name when she applied for State assistance. A couple years later, she slept with one of her brother's friends and got pregnant. After giving birth, she gave the baby up for adoption and never told her brother's friend that she had his baby. My fear is that if we do get divorced, that she may try to pull something similar with me. Can this information be used in court if it comes down to fighting for custody?
I cannot answer your question specifically to the laws of California as I am not licensed in that State. Generally pre-marital issues are not relevant to the divorce. The court will often view the premarital issues as something you should have known and considered prior to marriage and then prior to having a child with the person. If the issues were hidden from you there is more of a chance to put the issues before the judge. If you are allowed to put the issues before the court the facts presented appear to show a pattern of minimizing the role of the father in her children's lives. That is often a factor in custody disputes.