Does my 7 months old Baby requires Chinese Visa?

Hi, I am Indian, working in China under Z type with Resident permit. I planned to take my son ( who is 7 months old) and wife (she already have expired RESIDENT PERMIT ) to china under S1 type catrgory. Could you please advice, what are the documents i have to prepare for my Son and My wife?

Thanks in advance,
Niyaz KHAN