Lily is the oldest child in his lab. She has blond hair and blue eyes. He uses Lily as a ‘body’ or birthing mother for his experimental weapon, Mary. Yes, she was created by Father as a test tube subject. Lily only carried the fetus but feels strongly that Mary is her daughter even though they have no biological ties.
Father has also used her for his experiments and she suffers a dangerous mutation that she soon is unable to control… [more in future books!]