For generations they owned Kabul Industries which also served as a prison camp, as most of Otunia's criminals were sentences to work there by the Otunian authorities. Kabul Industries ceased to exist after the mines were blown up by a family member who sought revenge on another.
Lorn Kabul was the rightful heir to Kabul Industries. He was murdered by his own brother who then took over the operation.
Seth Kabul was Lorn's brother. He hated Lorn, because he felt that it should have been him and not Lorn who should have inherited the mining operation. Forming an alliance with the Empire, he killed his own brother and took over the enterprise.
Arista Kabul was Lorn's daughter. She sabotaged the mining operation shortly after Seth had taken it over to punish him for killing her father. She went off-planet afterwards.
Grissom the Gamorrean was not a member of the family as such. Originally an indentured worker in the mines, he swore to the dying Lorn Kabul that he would protect Arista. Having lost his own family to a lethal plague years back, Grissom in many ways regarded Arista as his own daughter.