Who was Osei Owusu as noted in the memoir, Aftershocks?

Osei Owusu was Nadia's father. Throughout her childhood, Nadia relied upon Osei for a sense of balance and identity. Her entire world was defined by him. When Osei married Anabel not long after Nadia's mother left, Nadia grew upset. She saw her stepmother as competition, and feared losing her father's love and attention.

Later, when Nadia was 13, her father grew ill and died of cancer. Afterwards, she felt the foundations of her reality shaking. Despite his absence, throughout her adolescence and adulthood, Nadia continued to shape her beliefs and identity around her memories of Osei. Her memoir, in large part, is guided by her relationship with him, and her grief over his passing.