In any proceeding pursuant to this title in which a petition has been filed to change the name of a minor, and both parents, if living, do not join in consent, the court may deny the petition in whole or in part if it finds that any portion of the proposed name change is not in the best interest of the child.
Source:
Section 1278.5, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=CCP§ionNum=1278.5..