We investigate the production of subject and object "who"- and "which"-questions in the Italian of 4- to 5-year-olds and report a subject/object asymmetry observed in other studies. We argue that this asymmetry stems from interference of the object copy in the AGREE relation between AgrS and the subject in the Spec of the verb phrase. We show that different avoidance strategies are attempted by the child to get around this interference, all boiling down to a double checking of agreement: AGREE and Spec-Head. Then, we evaluate our approach from a cross-linguistic perspective and offer an account of the differences observed across early languages. Because our account seems to call both for a grammatical and a processing explanation, we end with a critical discussion of this dichotomy.