Complex sentence: They lived on the Ghazwan near Taif while the Banu Sulaym attended nearby Medina, sharing a common cousin in the Al Yas branch of the Quraysh tribe.
Split into simpler sentences: They lived on the Ghazwan near Taif, and Banu Sulaym attended nearby Medina. They had in common cousin Al Yas that a branch of the Quraysh tribe.