Under California Law, "the child of a wife cohabiting with her husband is conclusively presumed to be a child of the marriage."  However, sometimes children are born out of wedlock or the mother's spouse is not the biological father.

Paternity of a child may be established independently, but it is most often addressed in the context of a request for child support. Establishing or refuting can have a substantial impact on support obligation, custody and visitation rights. If you are or think you may be the parent of a child, whether you have custody of that child or not, we will guide you through the process of establishing both paternity and determining the appropriate amount of child support. We can also help you to obtain the best possible custody and visitation arrangement for your child. If you need a paternity determination to protect your child, we can help.