Who is Ishmael al Soukori from The Haj and what is their importance?

Ishmael is the son of Ibrahim and his wife, Hagar. He was born in Palestine in 1936, and lived in the Village of Tabah. His family, the Soukori clan, had once been a part of the Wahhabi Bedouin tribe. When his mother is ordered to tend the family stalls in the markets of Lydda and Ramle, young Ishmael goes with her. He learns how to read, write and count and talks his father into sending him to school by telling him there are discrepancies in the books kept by his Uncle Farouk and brother Kamal. When Kamal attacks the boy, Hagar steps in. Ishmael says he didn't mention thirty parcels of land to Ibrahim, and he (Ishmael) wants half the rents from those lands.