You know who I am most envious of? People who learned to speak 2 languages from birth, in their homes, with their families. Man, if I could have given any gift to my children, it would have been the gift of being bilingual.
Children who live in homes whose language is other than English may encounter complications when they go off to child care or later, school. Even though the children learn to master English in no time, their parents may still be struggling to communicate in English, especially if they are new to this country. It is much harder for adults to learn a new language and communicate effectively in that new language than it is for younger people.
Ideally, all programs would have someone on staff who speaks the language of each family served. Ideal, yet not practical. I am often in programs that have 10-20 different languages of origin represented and some of those languages are not commonly learned here. As children get older, they often interpret for their parents, helping them navigate the world in English. This is great later, but not great when the children are still so little.
The best strategy that I know for working with families who speak a language that I do not speak (if they are still in the process of learning to communicate effectively in English) is patience and increased efforts at asking questions in a variety of ways to be sure that I am understood. I would also help them feel at ease by explaining that we are in the same boat; that I don’t speak their language confidently either (or at all).
Refrain from using “lingo” or “colloquialisms” as specialized language is even harder to understand for nonnative speakers. It is also a good idea to follow up an oral conversation with a written recap, just to be sure that everything is understood clearly. I guarantee that parents will appreciate all of the effort you are making on behalf of their families.