Hai,
Most of the times, family visit visa for mother in law are rejected by the emmigration. Anyway try it with the floowing procedure.
1. Arrange teh following documents:
a. Company letter (salary+NOC) from the husbands company
b. Labour contract copy
c. passport and ID card copies of you and husband (2 copies)
d. marriage certificate, preferably attested by the embassy and ministry of foreign affairs.(2 copies)
e. Passport copy of your mother.(your passport should contain your mothers name as such)
f. Main application form, duly filled.(original + 1 copy)
2. Go to the emmigration department, show the application to the main gate, go to the gate No.4, take a token showing the application, go to the counter. Your application will be checked there and you will be asked to pay QR.200 over a visa card. Keep the recipet with you.
3. Check teh application status in the moi site after two days.

Good luck!