Only child

An only child is a person with no siblings, either biological or adopted.

The term only child is generally applied only to those individuals who have never had siblings. An only child, however, may have half-siblings or stepsiblings who come along considerably late and still be considered an only child. Children with much older or younger siblings (generally ten or more years) may also have a similar family environment to only children.

Throughout history, only children were relatively uncommon. Over the 20th century in particular, birth rates and average family sizes fell sharply, for a number of reasons including increasing costs of raising children and more women having their first child later in life. The proportion of families in the U.S. with only children increased during the Great Depression but fell during the Post–World War II baby boom. After the Korean War ended in 1953, the South Korean government suggested citizens each have one or two children to boost economic prosperity, which resulted in significantly lowered birth rates and a larger number of only children to the country.

From 1979 to 2015, the one-child policy in the People's Republic of China restricted most parents to having only one child, although it was subject to local relaxations and individual circumstances.

Families may have an only child for a variety of reasons, including: personal preference, family planning, financial and emotional or physical health issues, desire to travel, stress in the family, educational advantages, late marriage, stability, focus, time constraints, fears over pregnancy, advanced age, illegitimate birth, infertility, divorce, and death of a sibling or parent.

Only children are sometimes said to be more likely to develop precocious interests (from spending more time with adults) and to feel lonely. Sometimes they compensate for the aloneness by developing a stronger relationship with themselves or developing an active fantasy life that includes imaginary friends. Children whose only siblings are much older than them sometimes report feeling like an only child. Advantages cited of having an only child are the decreased financial burden, the absence of any sibling rivalry, and that it becomes possible to take the child to an event suitable for their age without having to bring along a disinterested sibling. A disadvantage is that it can be harder for an only child to singlehandedly look after their aging parents.

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