Fascinating interview with Primatologist, 

Smithsonian Science Q&A: Macaques with Wolfgang Dittus 

What have the macaques taught you about primate behavior?

It might surprise people that family is the most important social bond or relationship that a macaque can have in its society. They take care of each other, and the females tend to form sisterhoods. Sisters help one another, and grandmothers and aunts are also there to assist.
Animals form social groups of closely related families that are, essentially, coalitions to defend their turf against neighboring families of similar structure. So, females have female bonded sisterhoods that are defense coalitions against other such groups. 

But, these relationships are a double-sided coin. The macaques will form social alliances and cliques within the larger group. This can lead to very strong jealousies within families. There is a social hierarchy that determines how the monkeys divide the group's food and other resources among themselves.
The mother is the highest ranking, followed by the youngest daughter, then the second youngest daughter, and so on. The reason why the youngest daughter—not the oldest—ranks second is because she is smaller and less experienced than her older siblings. The mother will come to the defense of the youngest sibling every time.
Interestingly enough, the young ones learn this quickly and will take advantage of this and act as though an older sibling has wronged them in some way. Then, mom swoops in to discipline the older sister! So, as long as mom is around, the younger sister dominates the older. Of course, when mom isn't around, the older sister will try to get back at the younger sister.