If a five-month-old baby does not make a sound when he laughs but his daily crying is normal, it may be normal and you can continue to observe; if the baby has not been pronouncing words, you need to consider the possibilities of vocal cord dysplasia, intellectual disability and autism. The speech development of babies around 5 months old should be able to produce mumbled word syllables, recognize human voices in daily life, and laugh and respond when teased. If the baby’s height, weight and neurological response are normal, and the baby can make sounds when crying, but only no sound when laughing, it is considered normal, and you can continue to observe and interact with the baby on time. If the baby continues to have no development, or even no voice when crying, poor interactive response, etc., it is recommended to seek timely medical evaluation to rule out the possibility of vocal cord dysplasia, intellectual disability and autism, and to intervene in a timely manner to avoid affecting the baby’s language development. Five-month-old babies do not make a sound when they laugh, there may also be other causes, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.