Study 1: The present work examined the connection between language and conceptual development, investigating whether false-belief reasoning (FBR) and source-monitoring ability (SMA) abilities within the theory of mind (ToM) framework constrained the comprehension of semantic and pragmatic knowledge (evidential scalar implicatures) encoded in the evidentiality structure (Papafragou et al., 2007). In addition, due to the nature of the linguistic background of the participant groups Spanish-dominant Aymara heritage children (HCH) and Spanish-dominant children (HCU), the current work examined whether bilingual children have an advantage in the development of the two target ToM abilities. A total of 21 HCH performed one semantic and one pragmatic Aymara evidentiality task, demonstrating that the semantic knowledge of Aymara evidentiality had a positive relationship with the acquisition of ToM abilities, as opposed to pragmatic knowledge. Regarding the development of the ToM abilities across groups, the bilingual population and 19 HCU performed two ToM tasks. The results showed that the linguistic background of the participants did not affect task results, suggesting that their ToM abilities were not constrained by their linguistic experience and promoting the idea that that the presence of an obligatory system to mark evidentiality does not increase the way that children develop Theory of Mind abilities. Study 2: The present study attempts to demonstrate that the evidentiality system in Aymara is subject to CLI due to the convergence of interpretable features in Aymara and Spanish, namely evidentiality and aspect, respectively, based on the Functional Convergence Hypothesis (Sanchez, 2004). 21 heritage- bilingual Aymara- Spanish children and a baseline group of 15 heritage- bilingual Aymara- Spanish adults performed two comprehensions forced choice tasks, one elicited production task, and one retelling story task in Aymara to examine whether the Spanish aspect influenced their Aymara discourse. In addition, to examine whether Aymara evidentiality modulated the Spanish discourse of the participants, the same groups and 19 Spanish-dominant children with a strong Aymara identity performed a Spanish version of the same tasks. The results showed that Aymara heritage children assigned evidential value to Spanish aspect morphemes and vice versa. Furthermore, in production, there was a high frequency of the use of different Spanish compound forms by the participants, suggesting the emergence of Spanish verbal structures that encode Aymara's evidentiality features. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]