Mr.Arwin Dimacali, your mother-in-law can issue an invitation letter to you, besides her invitation letter, a copy of her valid chinese residence visa and passport information page are also required. Please see the requirements for applying for China Tourirst Visa:
1. Applicant's passport with blank pages and at least 6 months validity left before expiration.

2. A truly and completely filled application form affixed with one passport-size or 2x2 colored photo, with white background, full-face front view, and no hat. Photo must be glued on the application form. Stapled pictures will not be accepted. Scanned photos will also not be accepted.

3. A copy of the round-trip plane ticket

4. Hotel reservation / invitation letter with a copy of the inviter's valid chinese residence visa and passport information page of inviter's

5. Previously used China visa in old or new passport (Only visa stickers will be accepted. Those with stamped visas must submit additional documents for first time China visa applicants. Please refer to the list below.)

6. For first time applicants to China (Philippine passport holders, 18 years old and above), they are required to provide the following:
a) original NBI clearance valid for travel abroad
b) original bank certificate with receipt or original passbook, updated within the month that you are applying or....
if your mother-in-law will will sponsor the trip, provide her bank certificate, sponsorship and invitation letter, copy of her valid residence visa and passport information page
c) for students, provide school ID
d) Personal appearance is required for those who are 16-21 years old.

7. The emergency contact information page in the applicant's passport should be filled out and photocopied.

8. Other documents required by the visa officers if necessary.