Sibling is neglecting dying mother. Any advice on how to handle this?

Well...a lot depends on whether she is safe to be left alone or not. And if mom is competent, she does get to decide on POA stuff. 50 bucks overdrawn might be a disaster in the making or might be trivial...do you know the details? We *all* rush to judgment sometimes, when we really need more info, as you can see from our answers! :-) Can you risk talking it out with your sister? Is there any chance sister is really there a lot more than Mom thinks or reports? (I'll be very happy to take back the "worthless leech" comment if it turns out not to be the case.)

What is your Mom diagnosed with? Does she have dementia? You and your other family members need to get to your Mom's and have a sit down to discuss the proper care for her. If your sister has POA and abusing your mom through neglect and fiscal irresponsibility, that right can be revoked. Do the right thing. At least have a video conference call with all parties (with google+ hangouts you can have up to 9 people on video calls at the same time!!).

Also, it sounds like you have some unforgiveness towards your sister that you need to deal with.

My mom made her POA

I did just visit her three weeks ago, and the sibling is a 39 year old female...It seemed all great to me and my other family members at the time ,this is all of the sudden and my mom and I can't agree on the outcome...she just begs me not to step in and says I should mind my business

If you possibly can, get the worthless leech off your mom's bank account - you can manage a bank account online no matter how far away if you have the info and set up bill pay and all. And contact the hospice SW with what you know. You can break promises to people if keeping them means they will be gravely harmed. Mom obviously wants to be at home rather than in a facility, and may just be afraid that telling on sibling will mean she gets taken away from her home. There may be more help available and maybe you can set up a webcam or other means of communication if you can't be there as much as you might like. Sibling needs the riot act read to him or her, and can be expected to be there and answer the phone and not leave mom alone for more time than is reasonable under the circumstances.

Who has POA? Given your Mom is on hospice, why not jump on a plane and investigate with your own eyes? You need to. Then you can call an elder attorney or at least the Dept of Health and Human Services to complain about elder abuse. You could also install a camera in her room which you could access on your computer to check in and see how she's being treated/doing.

Go buy a plane ticket and go see your dying mother. Why you would think your brother would be an eligible candidate to care for your Mom is beyond me, given it sounds like he may have a track record of being unreliable - unless, of course, he's one of the causalities of the dire global economy decline many of us find ourselves in.