i was wondering if some could help me. what are the sign of underactive thyroid in children. i have a five year old son who i think might have thyroid issues, but im not sure. underative thyroid run in the family. in fact i have and had unteated underactive thyroid when i was pregnant with him. not by choice, but because my ob at the time wouldnt check me for it. any way he has been have development delays, especially in his speech, and behavioral problems. any information would be helpful, i dont know what to do. we saw a developmental specialist a year ago because his pediatrician thought he was showing signs for autisms, but that was ruled out and was diagnosed with anxiety problems. he still is having major problem in school and going to see the specialist again in a few weeks. thank you for your time and hope to hear from you soon.