While at university, Ramphele became increasingly involved in student politics and anti-apartheid activism, becoming one of the founders of the Black Consciousness Movement (BCM), where she met Steve Biko, with whom she had a relationship. As a member of the BCM, she was crucially involved in organising and working with community development programmes. Biko and Ramphele had two children during their affair; Lerato Biko, born in 1974, and Hlumelo Biko, born in 1978. Lerato contracted fatal pneumonia when she was two months old. Their son Hlumelo Biko was born after Biko's death. Ramphele and her son would eventually work together in the Circle Group holding company for their family investments.