I am at work so I have to type English.
I just invited them to come to visit me. My husband and I both wrote a
letter to invite them and a letter to the visa officer. I prepared all my
legal documents and bank statement. Not more than what people usually do.
I think the most important thing is to have the relatives show the visa
officer that they have money and houses in China. There's no reason for them
to stay in the US.