Every Asuriní child is conceived as the outcome of a sexual relationship between its mother and Mahira (a mythic hero), which occurs during dreaming. When she has a dream of this kind, the woman knows she is pregnant; she must then have frequent sexual intercourse with her husband in order for his semen to make the foetus grow. All the men with whom the woman has sexual relations during his period are considered biological parents of the child.

Birth takes place inside the house in the presence of women and children only, since adult men should not have contact with the blood of the woman giving birth. The woman counts on the help of one or more midwives, generally her mother. The father of the new-born will only enter the house to see the baby several hours afterwards. The placenta and the umbilical cord are buried to prevent animals from eating them, which would harm the child.

Seclusion of the mother and father until the child's umbilical cord falls off involves a series of alimentary taboos, avoidance of heavy work and confinement to the house. The new-born child should be painted with genipap in order for it to grow more quickly. For the same reason, its father should sing to it every day.

Some days after the birth, the child receives a name, generally chosen by the grandparents who know the names of the ancestors. The name is always of a dead person, but does not appear to establish any relationship between the previous owner and the child. Names refer to animals, fruits, plants and so on. Traditionally a man had three or four names. Acquisition of the second name was related to the ceremony for piercing the lower lip, which allowed the boy to use the lip decoration and penis sheath. This ritual is no longer practised and the shaman is the only man to use the lip decoration.

Young couples marry at around 15 years of age. The ideal wives for a man are considered to be his father's sister daughter (FZD) and his sister's daughter (ZD). Most marriages are monogamous, but in the 1980s the anthropologist Lúcia Andrade noted the existence of two polygamic marriages, formed earlier in the 1960s.

In marrying, the young couple as a rule go to live in the wife's parents' residential section. If it is the boy's first marriage, he will end up living in his father-in-law's actual house. After a certain period - whose limit seems to be determined by the birth of the first child - the boy builds his own house, close to his that of his wife's parents. The son-in-law must maintain a relationship of obligation to his father-in-law, which implies co-operation in economic activities, political support, as well as distance and respect. The relationship between father-in-law and son-in-law is usually cordial but formal - a distance is maintained that marks the hierarchy existing between the two. A son-in-law must collaborate with his father-in-law in economic activities such as clearing swiddens. It is also common for them to leave together on more prolonged hunting trips involving sleeping in the forest for two or three nights. However, it should be stressed that the relation does not just involve the son-in-law's provision of bride service to his father-in-law, since normally they perform the activities in conjunction. This is a form of co-operation benefiting them both. The difference lies in the father-in-law's power to call upon his son-in-law for assistance: the latter would find it difficult to refuse his father-in-law's request.

This power of summoning help becomes an even more important political power in a society such as the Asuriní's, where, for example, institutions such as a village meeting space where all the men discuss and deliberate political and economic issues are absent. There is no chiefly figure with the ability to mobilize the village as a whole.

Thus, there is no figure or institution among the Asuriní enabling the activation of the entire village for deliberation and execution of political and economic decisions. Summoning power in this society seems to be restricted to the father-in-law/son-in-law relationship and therefore to the sphere of the residential sections. As a consequence, the political status of an Asuriní man is directly linked to his daughters' marriages.

As the man becomes older, marrying his sons and surrounding himself with sons-in-law, his political influence gradually increases. The larger the number of sons-in-law a man has, the larger the contingent he will be able to mobilize.

Other sources of prestige are shamanism and, in the past, warfare activity, which in combination was further able to strengthen an individual's importance.

A man's preparation for shamanism begins when he is still young, through his participation in 'tobacco festivals.' Taking part in these rituals also ensures the biological growth of individuals. Thus, if an adolescent boy is showing difficulties in growing, his parents take him to the festival for him to dance strenuously and acquire physical strength.

The rituals contribute to an Asuriní man's biological and social development. Basic knowledge of shamanism is indispensable to the man's social formation. It is not a topic just for specialists. Thus, the power to cure may be restricted, but knowledge of and contact with the Supernatural are constituent parts of the male personality. As a result, all Asuriní men are at least to some extent shamans.