This article provides a cross-cultural study of language socialization through sign language in three indigenous Mesoamerican communities. We explore whether child signers are socialized to use visual communicative practices as participants or observers. We present four conversations that illustrate how child signers are socialized into these practices. Child signers in our study acquire appropriate visual practices, even when they are primarily observers. But sign language socialization practices may be distinct from broader patterns of spoken language socialization in terms of participant frameworks. We find that recognition of child signers as full participants in sign conversation is shaped by a constellation of local child-rearing beliefs and language ecology dynamics.