Not much of what we know comes from direct experience but rather from others' testimony or input. Therefore, distinguishing trustworthy sources from those are not is an important skill both adults and children should posses in order not to be misled. One way to identify the credibility or reliability of the information is to focus on the source of the information, such as perceptual access or communication (hearsay). The present series of studies focus on the scope of children's evaluation of source information in verbal messages. While some languages, such as English, encode the source information by lexical means; i.e., I saw that he left, other languages such as Turkish or Bulgarian code that information by grammatical means; i.e, evidentiality markers. The cross-linguistic design (Turkish vs. English) in the present studies allows for exploring the interaction of language (evidential vs. non-evidential) with children's source reasoning and resistance to misinformation by others. Specifically, the studies explore whether children growing up in a language in which source cues are marked grammatically would be more alert to others' informational states compared to children growing up in a language which needs additional words to code the source distinctions. In a modified misinformation paradigm, the findings revealed that 4-, 6and 8-year old Turkish-speaking children were sensitive to whether the misinformation comes from perception and or communication. That is , Turkish children were more resistant to new information if it came from a communication (hearsay) source as opposed to a direct perception source. English-speaking children did not take the source into account until 8 years-of-age. Moreover, Turkish-speaking 4-year-olds were more resistant to misinformation when it came from a hearsay source when compared to their English-speaking peers. These findings reveal an influence of language in children's developing understanding of source information and evaluation of information by others. The results raise curious questions about the effect of language on children's non-verbal conceptual development for future directions.