Sandra Steenwijk is Anton's daughter and oldest child. Sandra is a precocious child who brings Anton a great deal of joy in the early years of her life and a great deal of guilt after his divorce from her mother. When Sandra is sixteen, she insists that Anton take her to Haarlem to see where her grandparents died. Anton does, and together they visit the memorial and the cemetery to see Truus's grave. Later, Sandra becomes pregnant and moves in with a man Anton disapproves of. However, they remain close and Sandra is clearly a source of joy and peace for Anton.