I heard that for the first time enter china,one have to be present physically will that option work?

hello ,i am a graduate from china and now going again for further study ,i have told my old university to send one invitation letter for my mum along with my one for a visit ,what i wanna ask is that will that be ok if i apply in the embassy on behalf of her rather than accompanying her with me as she is not physically 100 percent well at present ,another question the invitation letter coming directly from my university in their letter pad so in that do i have to show the bank statement for her for getting the visa .Thank you