Duplicate Survey reference in SurveyQuestion

SurveyQuestion has required references to Survey and SurveySection. SurveySection also has a required reference to Survey. Thus, SurveyQuestion ends up having two references to Survey: a direct one and an indirect one (thru SurveySection).

Assuming both references point to the same Survey: is it necessary to have a direct reference to Survey in SurveyQuestion?