As linguistic diversity increases in the U.S., it is essential for pre-kindergarten (pre-k) programs to expand their capacity to serve families whose home languages are not English. Family engagement is a key component of early childhood education; however, it is unclear whether family engagement practices uniformly benefit students from diverse backgrounds, including English Language Learners (ELL). In this mixed methods study, we explored whether teachers' family engagement practices were associated with ELL children's attendance and early learning, focusing on whether two aspects of the linguistic context--classroom composition of ELL students and teachers' practices for communicating in families' home languages--moderates these associations. Additionally, we used parent focus groups to shed light on ELL families' experiences with family engagement. We found consistent evidence that associations between teachers' family engagement practices and ELL children's attendance and socioemotional skills were moderated by classroom composition of ELL students. Specifically, family engagement practices were associated with better attendance and higher socioemotional skills among ELL children in minority ELL classrooms (less than 20% ELL) but not in classrooms with more ELL students (20% or more). Results aligned with themes from our qualitative analysis, which found that having few ELL families in the classroom made it difficult for ELL parents to make connections with other families, which might make it challenging to build a sense of community. This suggests that families without access to networks of linguistically similar peers at school might need additional support from teachers to feel welcome and encouraged to participate.