我是公民，父母綠卡，外婆86歲了，因為家裏種種原因，所以如果外婆來美和我一起住是最好的了。現在有下列幾個問題請教各位，希望能得到各位的幫助。
1. 以誰的名義邀請外婆來美比較好，我還是我媽？
-Only your mother can sponsor your 外婆 green card application.
2.外婆86歲了（從來沒出過國門），是否可以免麵試簽證？
-I think so because her age is old enough to use 中信銀行代簽.
See this link:
http://www.ecitic.com/bank/personal/chuguo/32.htm
3.如果需要經濟擔保，我父母沒有存款，隻能我和我先生共同擔保。
-Yes, your mother is the sponsor and you or your spouse can be co-sponsor (joint sponsor),
問題是：外婆年紀大了，如果來美國後生病的話，是不是因為我和我先生作了經濟擔保，所以我得承擔醫療費用？
-Technically yes, but she may get some kind of health insurance or short-term medical assistance based on your state policy.
4. 因為我已經是公民，所以是不是外婆來了以後我就可以幫她申請綠卡？
-No. But if your grandmother stay in US illegally, your mother has to become a US citizen and theu, your grandmother can file I-485.
期待各位的幫忙，在此先感謝各位了！
