Babies-

Weak musclesSlow motor development — taking longer than average to sit up, crawl and walkDelay in speakingQuiet, docile personalityProblems at birth, such as testicles that haven't descended into the scrotum

Boys and teenagers-

Taller than average statureLonger legs, shorter torso and broader hips compared with other boysAbsent, delayed or incomplete pubertyAfter puberty, less muscular bodies and less facial and body hair compared with other teensSmall, firm testiclesSmall penisEnlarged breast tissue (gynecomastia)Weak bonesLow energy levelsShynessDifficulty expressing feelings or socializingProblems with reading, writing, spelling or mathAttention problems