Please pay attention to the consular districts of China consulate in Laoag and China embassy in Manila, then you will know where you should apply for tourist visa.

You can find the requirements for tourist visa from this page, please read the information on this page carefully.

Personal appearance is required for applicants who are 16-21 years old. If your nieces are not at the age between 16-21, they don't need to appear in person.

To prevent child trafficking, Republic Act 7610 requires unaccompanied minors below 18 years old who are traveling abroad to secure a travel clearance from the Department of Social Welfare and Development. A Travel Clearance is not required if the minor is traveling with both his/her parents.