Sibling

A sibling is a relative that shares at least one parent with the subject. A male sibling is a brother and a female sibling is a sister. A person with no siblings is an only child. While some circumstances can cause siblings to be raised separately (such as foster care), most societies have siblings grow up together. This causes the development of strong emotional bonds, with siblinghood considered a unique type of relationship unto itself. The emotional bond between siblings is often complicated and is influenced by factors such as parental treatment, birth order, personality, and personal experiences outside the family. Medically, a full sibling is a first-degree relative and a half sibling is a second-degree relative as they are related by 50% and 25% respectively. The word sibling was reintroduced in 1903 in an article in Biometrika, as a translation for the German Geschwister, having not been used since 1425. Siblings or full siblings ([full] sisters or brothers) share the same biological parents. Full siblings are also the most common type of siblings. Twins are siblings that are born from the same pregnancy. Often, twins with a close relationship will develop a twin language from infanthood, a language only shared and understood between the two. Studies suggest that identical twins appear to display more twin talk than fraternal twins. At about 3 years of age, twin talk usually ends. Twins generally share a greater bond due to growing up together and being the same age. Half-siblings (half-sisters or half-brothers) are people who share one parent. They may share the same mother but different fathers (in which case they are known as uterine siblings or maternal half-siblings), or they may have the same father but different mothers (in which case, they are known as agnate siblings or paternal half-siblings. In law, the term consanguine is used in place of agnate). In law (and especially inheritance law), half-siblings have often been accorded treatment unequal to that of full siblings.