Next, the block actually names the relationship between that person and you. We'll go into more detail on that in just a moment. Same with your siblings. Notice that this is different from your traditional degree of kinship. According to the traditional measure you are 1st degree kin to your parents and children, but only 2d degree kin to your siblings.
Direct relatives measure lines of direct descent.
Anyone in that line will either be a direct ancestor, or a direct descendant of you, and in the chart I've colored all those folks in green. Collateral relatives share a common ancestor, but are not directly descended from or ancestral to each other. Now these categories are not mutually exclusive. For example, my great-grandparents were 2d cousins once removed from each other. That means that all their descendants are related to each other more than one way.