Banu Sa'd is a tribe from the Arabian Peninsula, specifically known for its historical significance in the early life of the Prophet Muhammad. This tribe is part of the larger Arab cultural and social structure and is recognized for its role in the upbringing of children, particularly through the practice of fostering. In Islamic tradition, Muhammad was sent to live with a woman from the Banu Sa'd tribe named Halima Sa'diyah during his early years. This experience is often highlighted as a formative period in his life, as it allowed him to grow up in a rural environment, which was believed to have contributed to his character and eloquence.