Your question raises two possibilities. One, your grandson has a sensitive temperament and finds noise and excitement upsetting. Generally, with time and patience youngsters like this tend to feel more comfortable. A second possibility is that there is a developmental delay in your grandson regarding socialization. When a child has one delay, such as speech, it is common for other delays to occur.
I recommend that your daughter consult her pediatrician so she can talk with him about several issues – namely, whether he makes eye contact, is able to give and receive affection, communicates with the adults in his world, demonstrates reasonable intelligence and is interested in other children. If the pediatrician finds him normal in these regards, chances are your grandson has a sensitive temperament.
Our parenting advice is given as suggestions only. We recommend you also consult your healthcare provider, and urge you to contact them immediately if your question is urgent or about a medical condition.