Congr!! Hurry up NSCERs

You'd better apply for a new passport for your mother as soon as you can since the old one may have got lost. In fact, it is faster to get a new one than to find the old one.
I don't understand why you sent your mother's passport to CIS. I renewed the visa for my in-laws for twice. However I did not remember this was required.
Anyway good luck.