How to keep dual citizenship when visiting USA

we are planning a visit to the USA for the first time in late November with our daughter who now holds USA and Chinese passports. we want to keep her Chinese citizenship for now, so we applied for a visa to the USA for her Chinese passport and received it already. however, we are unclear what the procedure is once we arrive in USA, where she is supposed to use her USA passport to enter the country. and how this will affect her status upon return to China -- ie, she will not have a stamp on her Chinese passport, so how to explain that to Chinese immigration? anyone have any experience with this? very much appreciate your help!!

You have the US Visa in her China Passport. So just use this passport to enter and exit the USA and you will have the stamp in the passport.

thanks for the  reply, but unfortunately it's not that easy. during the visa application interview, the staff at the US consulate said very clearly that she should use her China passport to leave China, but use her USA passport to enter the USA. that means that she will have a departure stamp from China in her Chinese passport, but no enty/exit from USA stamps. thus the dilemma and my question.