Kinship / Descent:
Kinship was very important to the Greeks. Families supported each other based on oikos (close family), genos (extended family / clan), and phantry (brother hood). Oikos and genos are pretty self-explanatory. Phantry encompasses blood-brothers and close friends. The Greeks stuck up for and supported their friends just as we do. Unlike us, however, cousins could marry each other. One could not, however, marry their parent or sibling. Lineage was mainly determined from the father's family, but royal blood was royal blood, and the mother's lineage was traced as well, and held in high regard. The main place for kinship and descent was political. A man from Athens could only be considered a citizen if he was a native, and never a slave. Women and servants could not be citizens, and thus had very little say in the government.