This Theorist Was an Only Child Who Was Very Isolated

This theorist was an only child who was very isolated and lonely during his childhood. He grew up to develop an interpersonal theory of personality, and in his writings he stated that social interaction with siblings was so important that only children have little hope of attaining full personality development. The name of this theorist is_______________

A) Eysenck
B) Sullivan
C) B.F. Skinner
D) Bandura