Gampopa

Gampopa Sonam Rinchen (1079–1153) is Tibetan Buddhist teacher - lama, holder of the Kagyu school, one of the four major schools of Tibetan Buddhism. 
He was the most important (or son like) student of Milarepa. 
In his young years Gampopa was a physician in Dagpo region of S. Tibet. Before studying under Milarepa, Gampopa had studied the Kadampa tradition, which belongs to gradual Mahayana path. He searched for, and eventually met Milarepa, and attained realization of ultimate reality under his guidance. 
Four of his disciples founded the four "major" Kagyu schools: