To elicit object pronominals, we used the syntactic island task (Varlokosta et al., 2014). In this task, participants were presented with pictures and for each picture, they were asked a question that triggers a reply with a because-clause containing a pronominal. The context strongly favors the use of a pronominal by making the antecedent very salient in the discourse. A picture was presented in which one animate character is preforming an action on another character or object. The experimenter described the picture in a sentence and then asked the child a why-question. The target response is a because-clause with a pronoun.
To elicit reflexive pronouns participants were presented pictures depicting a character doing a reflexive action. The participants were then asked "what is [this character] doing". The order of reflexive and object pronouns presentation was randomized. The target response is a simple sentence with a reflexive pronoun.