In In re Melissa H. (1974) 38 Cal.App.3d 173, the court stated, "under subdivision (d) of section 600 of the Welfare and Institutions Code, the jurisdiction of the juvenile court extends to any person whose home 'is' unfit. The use of the present tense verb indicates an intent that the unfitness exist at the time of the hearing; however, past events can aid in a determination of present unfitness."