Re: Buying Mortgaged Property
generally, no, you cannot. Many (most) mortgage loans have a due on sale clause that is activated if the title to the mortgaged property changes title.
You can enter into an agreement to purchase the land or you could she could ask the bank if they would release this portion of the total property from the lein so she can sell it.
I am not an attorney and any advice is not to be construed as legal advice. You might even want to ignore my advice. Actually, there are plenty of real attorneys that you might want to ignore as well.