First born siblings are more likely to develop better second language skills, according to a study of 1,200 bilingual children published earlier this summer in Frontiers in Psychology. The study focused on the theory that families with more than one child are thought to follow the resource-dilution model: children with fewer (or zero) siblings “achieve better grades at school and have a higher level of education than individuals from families with many children.”

First born children also have early childhoods without younger siblings, which means not sharing parental time and attention, and more financial resources for early education. However, it is also thought that the eldest sibling in immigrant families plays a crucial role in incorporating the family into the host culture.

With the resource-dilution model in mind, researchers designed a study to address whether attending an early education institution would mediate “the relationship between number of siblings and second language skills,” and also if better second language skills could be expected of the eldest sibling or the younger siblings.

The participants, who were families with a child between the age of two-and-a-half and three years old, lived in the city of Basel in the German-speaking part of Switzerland. The questionnaire was sent out to qualifying families over the course of four years (2009 to 2012), with a final sample of 1,209 children, 39% of which were an only child, 42% had one sibling, and the remaining 19% had two or more siblings. Researchers took into consideration the level of German language skills by employing a standardized questionnaire.

The most important distinction in family structure was first born children (56%) and later-born children (44%). Early education was also considered in the study, with about 10 hours per week spent there.

This study took a snapshot of children in these families and compared them to each other; an improved possible study would follow siblings throughout their childhood to determine second language skills. Researchers noted that siblings take on different roles in different cultures, and cultures with older siblings raising younger ones might be of special interest in a future study.

Through the use of statistical analysis, researchers found that lower second language skills persisted when an individual had more siblings, and that children without an older sibling had better second language skills than those who did. The more siblings an individual has, the less time was spent at an early education institution; these institutions accounted for a 15% increase in second language skills.

An important distinction is the availability of language resources for immigrant families. They cannot pass down the second language to their child or children, and so must purchase the education resources necessary to learn the host language. It is then especially important to provide immigrant families with the financial resources to educate their children.

“Considering that families from immigrant backgrounds have fewer financial resources, and that these resources influence the children’s level of development, it seems all the more important that immigrant families with many children are financially supported so that their children are offered the best opportunities possible for their academic careers,” the researchers concluded. “Given the results of this study, promoting the attendance of early education institutions is an efficient way of achieving this goal.”