This research examined the conditions under which codesigned approaches to educator professional learning in multilingual, birth to five settings were accessible and supportive of children's social and emotional development across diverse types of Australian early childhood services. The research sites, in the suburbs of a capital city, comprised a long day childcare center, two short term informal community creches for birth to 5-year-old children of migrants and refugees attending English classes, and a family hub short term informal community creche for children of Afghan refugees. Professional learning mentors visited the participating sites eight times for 2 h every 2 weeks for 16 Weeks in 2021, demonstrating resources and strategies to assist young children to identify their own and others' emotions and engage with social settings. Over 20 weeks, 97 participants provided data, commencing before and extending after the professional learning program. Participants included professional learning mentors, staff and volunteers, parents, and children via observation. Using Reggio Emilia principles, the research identified that professional learning, flexibly delivered over time, enabled educators and volunteers to build their social and emotional development knowledge, and to try resources and strategies with children in their care. Recruiting educators who shared children's home or community languages, in addition to professional learning, supported multilingual children to engage with emotional literacy resources, while still developing spoken English. The research affirmed that educators, volunteers, parents, and children benefitted from a sustained focus on children's social and emotional development in the early childhood education and care settings.