Apply for S1 Before or After Arrival on My X1 Visa

Hello,
I will be studying in at Qinghua University for and will bring my two young children and wife. The China Consulate site states that I need to submit my residence permit along with other documentation in order to obtain S1 entry permits for them, but based on my understanding, I cannot obtain this residence permit until I arrive in China. I am confused.
Are my family members able to enter China with me? If so, what visa should they have?

Thanks,