In this talk I will present findings from two experiments conducted in Hebrew on the acquisition of relative clauses by children (mean age 4;5). Relative clauses have been extensively studied within the field of language acquisition both because of the apparent difficulty children have in comprehending them (Sheldon, 1974) and because of their relevance to theories of syntactic development and breakdown. Many studies have shown that children have special difficulty with object relative clauses (show me the doctor that the soldier is drawing). In addition, an intruiging discrepency betwen production and comprehension wherein production precedes comprehension is also reported. One prominant account for patterns of relative clause acquisition is that children lack movement abilities(the ability to connect a moved element with its trace)thus conceptualizing the difficulty as a developmental stage having to so with the lack of certain syntactic abilities. However, a reanalysis of previous studies in addition to adult data showing that adults also have difficulty with relative clauses seem to weaken this claim. The presented experiments tested both production and comprehension of relative clauses, with and without resumptive pronouns (which are not supposed to involve movement in Hebrew). The results demonstrate a novel error pattern, correlating with the production of relative clauses with resumptive pronouns. In addition, preliminary results demonstrate that some of the children do not comprehend the 'non-movement' resumptive structure as well. Overall, the results confirmed the need to look for explanatory factors other than movement to account for relative clause acquisition, and underline the importance of close analysis of error patterns. I shall discuss some possible interpretations, focusing on the possibility of developmental sub-stages in the acquisition of relative clauses and the potential role of processing limitations in addition to structural limitations in accounting for both the individual variance revealed by these studies and the lag between production and comprehension.