Cal. Fam. Code § 5000

(a) When a petition or comparable pleading pursuant to this chapter is filed in a court of this state, the local child support agency or petitioner may either (1) request the issuance of a summons or (2) request the court to issue an order requiring the respondent to appear personally at a specified time and place to show cause why an order should not be issued as prayed in the petition or comparable pleading on file.
(b) If a summons is issued for a petition or comparable pleading pursuant to this chapter, the local child support agency or petitioner shall cause a copy of the summons, petition, and other documents to be served upon the respondent according to law.
(c) If an order to show cause is issued on a petition or comparable pleading pursuant to this chapter requiring the respondent to appear at a specified time and place to respond to the petition, a copy of the order to show cause, the petition, and other documents shall be served upon the respondent at least 15 days prior to the hearing.
(d) A petition or comparable pleading pursuant to this chapter served upon a respondent in accordance with this section shall be accompanied by a blank responsive form that shall permit the respondent to answer the petition and raise any defenses by checking applicable boxes and by a blank income and expense declaration or simplified financial statement together with instructions for completion of the forms.