So, we've finally settled on a course of action. We've come up with a plan to reduce her debt. She will probably not be able to get a new credit card for a few years. But with her social security and the financial assistance from me and her sons, she should be able to get by.
Unfortunately, we can't afford my niece's tuition and other upkeep while also financially supporting my sister. So, at the end of this school year, she'll be going back to her parents.
Meanwhile, my sister can't continue to be supported by others. She'll need to do something eventually. But hopefully, we can figure that out before I can't afford to support her anymore.