The vascular family refers to a group of vessels fed by a primary branch of the aorta or branches of the vessel that are being punctured. They are vessels that arise directly off the aorta or vessel puncture. For example, the in nominate defines one particular vascular family. First order is the main artery in a vascular family, second order is the branch off the main artery, while third order, is the next branch off the second order and so on.