This preliminary study examines the languages used by parents with their children in Malay, Chinese Foochow and Indian Tamil families to find out how the similarity or dissimilarity in parents' ethnic language influenced the choice of language transmitted to children and how far standard languages have permeated the family domain in Kuching City in the Malaysian state of Sarawak. Standard languages refer to the three main written languages taught in the school system, namely, English, Bahasa Malaysia (Malay language) and Chinese Mandarin. Interviews were conducted with 17 families (6 Malay, 6 Chinese Foochow, 5 Indian Tamil). The results showed that the ethnic language is mostly still retained in the Malay and Indian Tamil families but has been pushed out by English and Mandarin Chinese in Chinese Foochow families. English has emerged in parental communication with children to different extents across ethnic group. Bahasa Malaysia, on the other hand, is spoken in Malay families with parents from West Malaysia. Factors found to be influencing the parental decision on language to use with their children include similarity/dissimilarity of the couple's ethnic languages, their educational background, family and social linguistic environment, instrumental value of languages and ethnic identity. (Contains 3 tables and 1 endnote.)