<human>:  Who was Donald Winnicott?
<bot>: Donald Winnicott was a British paediatrician who developed the theory of object relations. Object relations theory focuses on the relationship between the child and the mother, and how the child develops an understanding of the world. The theory is important because it explains how children develop the capacity to form mental representations of objects, such as people and places, and how they develop the ability to make mental distinctions between these representations.