Marriage. There are tribal moieties that do not regulate matrimony, having only a ceremonial role. It has been observed by researchers of various Gê groups of central Brazil that, among such segmentary societies, there occur nonexogamic but ceremonial and cosmological moieties.
There do not appear to be impediments to matrimony with parallel or cross cousins, but marriage between people belonging to different generations is censured, even though there are several such unions. The avunculate is important and cases of levirate and sororate occur. There are also cases of sororal polygny. Monogamy is generally prevalent, but there are frequent separations and successive unions. There is a tendency toward village endogamy.
Domestic Unit. Until about 1960 the domestic unit was composed of an extended matrilineal family occupying just one house. Even then, however, there were exceptions to the rule. Today there is a tendency for siblings (or married sons, if the parents are alive) to occupy houses next door or nearby, such nuclear-family households resulting from the subdivision of larger groups. These, according to common law, must always occupy the identical territory inside the area of the village. Individuals of the same extended family have their burial grounds located in the same territory of the general cemetery.
Inheritance. The right to ownership of a house that shelters a household in the territory of an extended family was transmitted from mothers to daughters, even though the constructed dwellings were, and still are, burned after the death of the head of the household, either man or woman. Some objects of individual use accompany the dead person, some are given to the burial party (which may or may not include the person's relatives). The remaining objects go to the family, which, however, generally prefers to give them away, even though they may be very valuable. A man can acquire for his son the right to take part in rituals performed with specific dance masks.
Socialization. The children receive an informal education at home and learn from their maternal and paternal relatives to conduct themselves according to the expectations of Karajá society. Their relatives teach them the techniques of domestic jobs as well as those of subsistence and handicraft. The children start to receive notions about myths, cosmology, and tribal history.
The feminine relatives exercise a great influence on the socialization of the young people, even with respect to the boys, a pattern that continues as they become young men. At times, married men show more solidarity with their mothers and sisters than they do with their wives. Between 10 and 12 years of age, boys start to receive a more formal education on topics concerning religion and ethical questions related to consuetudinary law after their solemn entrance into the men's house at the feast of Hetohokã ("Big House").
Youngsters of both sexes attend regional public schools and/or bilingual schools for the Karajá. Some of the older boys (those over 15 years of age) have attended schools in Goiânia, the capital of the state of Goiás.
The use of corporal punishment has always been rare because the Karajá prefer to treat the improper behavior of youngsters ironically, inducing them to avoid being ridiculed. This method of correction persists with respect to adults: Karajá women normally laugh in a screeching and sarcastic manner at everyday events that involve someone's unacceptable behavior.