Who is Richard Steven Fuller from Don't Let's Go to the Dogs Tonight: An African Childhood and what is their importance?

Richard is the Fuller's final child. During a difficult pregnancy, Mum is hospitalized for months before the baby's birth. When he is finally born Vanessa and Bobo are ecstatic, but their joy does not last long. The baby soon dies in the hospital, without the girls ever seeing him. After this death, Mum's mental illness spirals out of control.