Oh Trish, what a mess!
And for those in the US who don't know - bio-mum would be eligible for subsidised medications via social sercurity, each prescription need only cost $5.50 or thereabouts and after a while (if you notch up enough for the family) it's free, I think (the rules keep changing). Of course, if you're really bad at managing your paperwork, it's really easy to get into strife with our social security system, she could have chosen to try to live outside it.
So if bio-mum hasn't even kept $5.50 aside, it's a worry.
Trish, my 'vibe' is telling me, she is trying to extract every cent of support elsewhere, to avoid spending wherever she can. My friend's foster son's famiy does the same thing to her and not just with money. Anything the kid needs that the family privately don't consider important or necessary, they will gratefully accept from the foster mum and will use (until it goes missing or gets trashed) but they won't get it themselves, nor with they replace it. Not if there is someone else who is more willing to fork out for it.
The phone thing - it's possible she might be eligible for a landline service due to health emergency issues. Relying on mobile phones is crazy, when you're broke. Reception is a huge issue, for one thing. Land lines are so much cheaper to run. It is so easy to blow out your phone bill with mobile. difficult child 1 has finally got this message and at last has a landline in. Poor reception where he lives has also flattened his mobile's batteries (the phone is constantly trying to 'find' the network, it chews through a lot of power to do so).
From what you've said - unless you can be certian that bio-mum is able to cope emotionally with the soiling, it could well be that having to bounce back and forth between the two households is aggravating the encopresis; a kid with anxiety plus a mother who isn't coping with the problem is almost a recipe for disaster, the problem will self-perpetuate. Added to this, I think you said in another post that bio-mum uses your place as a threat or punishment for Little Cherub. The poor kid is probably really confused by it all; a bit of stability would be really good.
That said - I really don't know. Bio-mum does need to really try, because even if you resolve the encopresis, it won't get easier when Little Cherub is in her teens. She can't just grab every opportunity to opt out just because she's having a bad day.
Marg