In Tibet a young man lives with his older brother, who is married. The younger brother eventually begins to think about setting up his own tent, and taking his share of the yak and fields of grass. One night his brother's wife gives him her necklace. In Tibetan culture this is an invitation for him to become her second husband. If he accepts, he will remain with his brother and share the same tent. His sister-in-law is offering him .

His sister-in-law is offering him polyandry and the opportunity to keep the family property as one.

Explanation:

Fraternal polyandry is commonly found among Tibetan families. Polyandry consists of one woman marrying more than one man. Fraternal polyandry consists of a woman marrying brothers from the same family.

In the scenario described in the passage, the advantage to the younger brother's acceptance of her proposal is that they will be able to keep the whole family herd and land rather than dividing them between the brothers. This creates a large and strong family and property unit.

im sorry i dont know a lot of this but ill try my best

h,c.b.e.d.f.a.g