Marriage. The Yawalapití are exogamous: they can't marry a person from their village, so they look for partners in neighboring villages belonging to the Kamayura, Kalapalo, Kuikuru, and Mehinaku groups. A young Yawalapití man lives with his bride's family for one year and helps his future father-in-law. He is not allowed to talk directly to his father-in-law, laugh in his presence, or call him by his name. Looking at his future mother-in-law is also forbidden, but he has to give her the best fish from his catch. He presents his future father-in-law with a loin-string made of snail shells. This is the bride-price. Only then is he allowed to take his bride to his village as a wife. Sometimes the couple settles in the bride's home. Polygyny is common, and not limited to chiefs. Men, as a rule, have two or three wives, who are often sisters or cousins.
There is no marriage ceremony. Men marry at the age of about 20 years, girls after completing the female initiation ritual. Although unmarried young women are allowed to have sexual intercourse with anyone, an unwed mother is not acceptable in the community; the newborn baby must be therefore killed. The unmarried woman is not assisted during labor and she kills the baby herself. After this, she is again accepted in the community.
For girls, the choice of a marriage partner is made by their parents. When adultery is committed and the husband finds out, he beats his wife. When the husband is caught, his wife laughs at him. Childless marriages are dissolved, and the partners have to remarry. The community does not tolerate unmarried adults. A disabled baby is killed, as a rule, by his or her uncle.
Domestic Unit. Each maloca is occupied by one extended family. Residence is bilocal or, more often, patrilocal.
Inheritance. Each man and woman own their personal belongings such as weapons, hooks, and hammocks. Large manioc-flour containers and ceremonial adornments are kept by the head of the maloca and are given to anybody who needs them.
Socialization. Children are raised at home, where infants are looked after by their mothers. When they get older, grandparents and older brothers and sisters are also involved. A boy of 11 to 12 years of age already does and knows things as a man. He gains his knowledge by observing his father. A father never teaches or punishes his son. They talk together as adults. The Brazilian government is exerting pressure on Chief Aritana to send the Yawalapití children to schools in Brasília. Teachers have on occasion come from the Leonardo Villas Boas Indian Post to instruct children.