Previous studies have found that Hebrew-speaking children accurately comprehend object relatives (OR) with an embedded non-referential arbitrary subject pronoun (ASP). The facilitation of ORs with embedded pronouns is expected both from a discourse-pragmatics perspective and within a syntax-based locality approach. However, the specific effect of ASP might also be driven by a mismatch in grammatical features between the head noun and the pronoun, or by its relatively undemanding referential properties. We tested these possibilities by comparing ORs whose embedded subject is either ASP, a referential pronoun, or a lexical noun phrase. In all conditions, grammatical features were controlled. In a referent-identification task, the matching features made ORs with embedded pronouns difficult for five-year-olds. Accuracy was particularly low when the embedded pronoun was referential. These results indicate that embedded pronouns do not facilitate ORs across the board, and that the referential properties of pronouns affect OR processing.