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A 14-year-old boy is significantly shorter than his peers and has not begun puberty. His father was a "late bloomer." Exam shows Tanner stage 1 with bone age of 11.5 years. Growth velocity is 5 cm/year. TSH, IGF-1, and CBC are normal. Which of the following is the most likely diagnosis?
A 14-month-old boy is not walking yet. He sat without support at 6 months, crawled at 10 months, stands holding furniture, uses a pincer grasp, and waves bye-bye. No dysmorphic features. Growth is at the 50th percentile. The most likely explanation is:
A 15-month-old boy's diet consists primarily of cow's milk (4–5 cups daily) and crackers. He has pale conjunctivae. Labs: Hb 8.2 g/dL, MCV 68 fL, serum iron 25 μg/dL, TIBC 450 μg/dL, ferritin 8 ng/mL. The most likely explanation is:
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