Bilateral descent means that family membership and connections are traced through both the father's and mother's sides equally. Both sides of the family are important for emotional support and for passing down property or wealth. This system recognizes relatives from both parents' families as equally important.

This type of family system is found in places like West Africa, India, Australia, and Polynesia. It can be helpful for families living in challenging environments because it allows them to rely on relatives from two different family groups spread across a wider area.