You would need to create a HeadOfHousehold and a DependentInHousehold class; maybe both have a Person field. You could have a HeadOfHousehold field in the dependent class and a dependent (or, maybe better, a List<DependentInHousehold>) field in the HeadOfHousehold class.
Design your head and dependent classes before you try to put the whole thing together. What you have might be incompatible with those two classes, so you may find you have to lose a lot of what you have already written.
subject: help converting my code into classes and arrays