A prenuptial agreement is an agreement between spouses before marriage as to how they shall divide and characterize property and liabilities which they anticipate to occur during marriage.  Under Washington law, parties may enter into legal contracts which govern all financial aspects of their relationship.  The legal requirements of a valid prenuptial agreement include full disclosure, fairness, and ability to have independent counsel.  However, a prenuptial agreement may not be enforced as to certain personal aspects of a marital relationship. Specifically, a prenuptial agreement may not be enforced when it attempts to provide a specific level of child support or the favoring of one parent over the other in a child custody matter.  The court has the ultimate jurisdiction over any agreements concerning the children of the parties, regardless of what the parties agreed to in their prenuptial agreement.