The conservator of an adult, or any person authorized to file a petition for the appointment of a conservator under paragraphs (2) to (5), inclusive, of subdivision (a) of Section 1820, may file a petition under this chapter for appointment of a limited conservator authorized to consent to the sterilization of an adult with a developmental disability. The content of the petition under this chapter shall conform to the provisions of Section 1821 and in addition allege that the person for whom sterilization is proposed has a developmental disability as defined in Section 1420 and shall allege specific reasons why court-authorized sterilization is deemed necessary. A petition under this chapter shall be considered separately from any contemporaneous petition for appointment of a conservator under this division.