Perminant resident

My wife is a Chinese national, her sister is also, my wifes sister married a forigner ( German) they had a child who is now 9 years old. After birth the forigner got the child a germen passport, the child does not have a Chinese sitizen residents card and can not leave China without getting a visitors visa upon his return. How can my sister in law get her son a Chinese residents card?

Thanks in advance