Reversal was required where juvenile court failed to determine biological paternity of child following alleged father’s request. The minor was declared a dependent after his mother abandoned him. Mother named R.P. as an alleged father, but his whereabouts were unknown. R.P. was located prior to the permanency planning hearing, and appeared, requesting paternity testing. The court granted the request but required R.P. to pay for testing. R.P. filed a JV-505 form requesting testing and stating that he wished to meet his paternal obligations if he was found to be the father. On appeal, R.P. contended that the juvenile court erred in failing to determine whether he was the minor’s biological father. The appellate court agreed and reversed the orders. California Rules of Court, rule 5.635 provides that if there has been no prior determination of parentage, the court must take appropriate steps to make such a determination. If a person appears at a dependency hearing and requests a judgment of parentage on Form JV-505, the court must determine whether that person is a biological parent and whether that person is the presumed parent if requested. Since R.P. made the request, the court was obligated to determine biological paternity. The court’s failure to do so violated California Rules of Court, rule 5.635 and required reversal.