This paper explores some possible interpretations of subject/object in child language, pointing out some potential problems in recent works within the minimalist framework and suggesting different views on it. Particularly, we will focus on how to identify and/or license objects, since most of the studies relevant to this issue have accounted for subjects only. Discussing the results of the studies on child language data, we will show that previous syntactic explanations on subjects, which have seemed quite attractive and refined, may not hold when accounting for objects and various aspects and properties of arguments in those child languages. In doing so, we will suggest and support a performance-based account, a discourse-based account, and a markedness account.