Marriage. Mailu marriages are arranged through betrothal, often when the girl is still quite young but usually when she has reached her mid-teens. The boy's family provides a series of gifts of increasing value over time, and both families participate in roughly equivalent food exchanges. Upon betrothal, both the boy and girl are expected to remain celibate—an affair by either one is sufficient to nullify the betrothal. Bride-wealth is paid in pigs, tobacco, and other items of locally recognized wealth. Since pigs can only be given away at feasts, at some point prior to the actual marriage the contracting parents of the betrothed pair will use the occasion of a maduna to make this gift. Marriage itself is not marked by elaborate ceremony: the bride prepares a meal for her betrothed in his father's house, then returns to her own for an interval of about a week. After that time, the marriage may be consummated, and the bride leaves her family home to live in her father-in-law's house, assuming membership in his clan. With marriage, a man enters into avoidance relations with certain of his wife's kin, most particularly with her older sister. Polygyny is permitted but rarely practiced, due to the great expense of pig-based bride-wealth entailed by Marriage. Adultery is considered a grievous offense for both men and women, but the punishment of an adulterous wife—a severe beating, even death—is far more onerous than the public censure and gossip that serves as punishment for a man's adultery. Divorce appears to be possible but rare.
Inheritance. Personal ornaments and wealth are inherited by a man's "real," as opposed to his classificatory, brothers. His coconut palms are passed to his brothers and his sons. The ownership of a house passes to the eldest surviving son. Women do not hold or inherit property, except in cases where a woman's father dies without sons.
Socialization. During their early years, Mailu children are cared for by their mothers and other female members of the household. Children enjoy a great degree of independence, rarely being corrected or chastised and generally being left free to indulge in games and sport. Boys are given miniature boats, similar in design to those used by their elders on the seas, and they are also provided with small versions of hunting and fishing nets and spears. For both boys and girls, early training in their adult roles is acquired by observing their elders at their daily tasks and by helping out when they possess sufficient skill and interest; this participation is allowed to develop at its own pace. Both boys and girls have their ears (and, formerly, the nasal septum) pierced shortly after birth. At about the age of 4, girls begin to undergo the long process of body tattooing, which culminates when they have attained marriageable age with the tattooing of their faces—done in conjunction with women-only feasts. Male initiation, which once was an important ritual event and required the acquisition of human heads during a raid, is no longer practiced. Infanticide is practiced when twins are born—the younger twin is killed—or when the mother dies in childbirth, as well as in the case of an illegitimate birth.