the only son or daughter born to a couple; an only child

a child born of parents not married to each other; illegitimate son or daughter

an only child who is a son

Children born to parents who are not legally married to each other.

children born in wedlock or within a legal marriage relationship

two siblings or offspring born of the same pregnancy; see also [[双胞胎|雙胞胎|shuang1 bao1 tai1]]

The population planning policy of China which generally restricted families to having only one child

two babies born from the same pregnancy; also used to refer to two people who were born at the same time to the same mother

To have a child via a surrogate mother; originally used when a wife was infertile to describe seeking an heir through another woman.

A child born to parents who are not legally married.

to get married and have children; to start a family

the last son born to an elderly couple

(literary) servant born into a household and raised as a slave

one's own biological children, as opposed to children who are adopted

child born after the death of his or her father