Weird family math problem

Question

Lets say there is a world with only 8 people. 4 men and 4 women. Those people each couple up with each other. One man to one woman. Each couple can only have one child. Each child grows into adulthood and can also only have one child. How many generations are possible without any descendants having to be coupled with a 1st or second cousins.

Answer 1

This question is interesting, and requires you to visualize the answer. See below:

Couple 1 Couple 2 Couple 3 Couple 4

Couple 1&2 Children Couple 3&4 Children

Last Generation of Non-Familial Bonds

4th Generation gets Familial

Hope this helps.