Sibling

A sibling is a person with whom one shares one or both parents. The term is used for both male and female relatives: 'walaal' and 'walaalo' or 'walaashiis' when the female is specified. This relationship is one of kinship and family, and forms part of the most common structures within households.

The sibling relationship functions differently across societies in terms of inheritance rights, responsibility for raising younger members, and the degree of family name use. In many Somali communities, older siblings are expected to take part in raising younger ones.

Types of siblinghood

When both parents are the same, the siblings are called full siblings. When only one parent is shared, they are known as half-siblings—for example, children with the same father but different mothers. There are also step-siblings, related by marriage rather than by blood, and adopted siblings.

Birth order

The terms 'First-born', 'Second-born', and 'Third-born' refer to the order of birth within a family. Some research in social psychology has attempted to link birth order to personality or educational achievement, but findings remain inconsistent.

Biology and genetics

Full siblings share on average about half the genetic variation inherited from each parent, while half-siblings share a smaller proportion. Offspring from the same egg share identical genetic material. This information is used in studies of family health and research into hereditary disease.

Social and religious use

In both Somali and Arabic, the term 'walaal' is also used in a broader sense to mean a religious bond or friendship, as when believers call one another siblings. Under Islamic law, siblings have a defined share of inheritance, determined by the existence of children and parents.