California Code, Probate Code - PROB § 13659

Except as provided in Section 13658, no inventory and appraisal of the estate of the deceased spouse is required in a proceeding under this chapter. However, within three months after the filing of a petition under this chapter, or within such further time as the court or judge for reasonable cause may allow, the petitioner may file with the clerk of the court an inventory and appraisal made as provided in Part 3 (commencing with Section 8800) of Division 7. The petitioner may appraise the assets which a personal representative could appraise under Section 8901.