Almost all books and case studies of bilingual children assume a two parent family. By accident and not by intention, this tends to lead to the assumption that a one-parent family has much less chance, or no chance of raising a child bilingually.
It is possible to raise a child bilingually inside a one-parent family. This is simply because a child's bilingualism may be acquired outside the mother-child or father-child relationship. What languages do the brothers and sisters speak? What language do the uncles and aunts, neighbours and friends speak to the child? Does the child go to a nursery school or a school where a different language is spoken from the home? What is the dominant language of the community? If a child has sufficient experience of a different language from that of the home, such a child may become bilingual with unsuspected ease. If, for example, the mother speaks one language continuously to the child, the child may receive sufficient experience of a second language in a nursery school, in the street and in school to ensure dual language development.