请问8老师，我母亲于2008年申请我姐姐（公民已婚子女）一家移民， 仍在排期等待中，妈妈刚过世，是否整个case 就失效了？ 我咨询了几个律师，说法各不同。
-Depends. If the I-130 has been approved before your mother passed away, then it is still valid as long as the substitute sponsor can be found to take over the case by submitting completed Form I-864. In your case, you can be the substitute sponsor if you are a US citizen or green card holder and you or your family have enough money to sponsor your sister.
But if the I-130 was not approved before your mother passed away, then it is void.
Read these links for some more information:
http://www.uscis.gov/green-card/green-card-through-family/humanitarian-reinstatement
http://www.immihelp.com/affidavit-of-support/substitute-sponsor-death-original-sponsor.html
