Lateral Sacral artery is a branch of
Anterior division of Internal Iliac artery
Posterior division of Internal Iliac artery
External Iliac artery
Direct branch from Common Iliac artery
Lateral Sacral artery is a branch of Posterior division of Internal Iliac artery. Other branches of Posterior division of Internal Iliac artery are

Superior gluteal Artery
Iliolumbar artery