Q. A mother brings her three-year-old to the pediatrician. She says her son has been crying, rubbing his forearm, and refusing to let her look at his arm. She states that as far as she knows, he did not fall or hurt his arm. This child’s medical history is significant for normal, full-term birth, and satisfactory achievement of developmental milestones. However, his record shows poor dentition and two previous instances of skeletal fracture. Upon inspection, the posterior area of his forearm is tender and erythematous. He has a bluish discoloration to the sclera and diminished auditory acuity. Which of the following is the most likely diagnosis?