mdmm,
If she overstayed, she might get deported and barred entry for a year. Here's a link from this forum about another American's case:
http://www.canadavisa.com/canada-immigration-discussion-board/complicated-situation-for-an-american-t24183.0.html
You might be able to extend her stay here too by exiting at the border for probably a day or two and coming right back in. It might be worth a try. You can call CIC though just to be sure of your possible options and if she's not capable of working anymore then maybe the officer at the port of entry will not think she's staying longer because she's going to work here.
If she overstayed, she might get deported and barred entry for a year. Here's a link from this forum about another American's case:
http://www.canadavisa.com/canada-immigration-discussion-board/complicated-situation-for-an-american-t24183.0.html
You might be able to extend her stay here too by exiting at the border for probably a day or two and coming right back in. It might be worth a try. You can call CIC though just to be sure of your possible options and if she's not capable of working anymore then maybe the officer at the port of entry will not think she's staying longer because she's going to work here.