How to convince adult child to pay for their keep

I’m asking advice for a close friend of ours. Let me give some background first. They have a 24 year old daughter that lives with them in the United States. She is the single mom of a 3 year old. Several years ago, she ran away from home and lived in a motel with a man for several years. They had a baby together. The man was abusive and a year and a half ago she came back with the baby and has lived with her parents since.

Her parents have provided everything for her and her daughter since their return. The parents have several other children with disabilities living in the home and are very tight financially. Their daughter has never once thanked them or shown any gratitude for how they have provided for both her and her toddler these past several years. She has also never taken initiative to find a job or contribute in any way.

The daughter has a long history of pathological lying. She refuses to ever see herself in the wrong. Everything is always someone else’s fault. She believes she is entitled to the care and finances of others. She jumps from person to person when she is not with her parents that feel sorry for her for a bit then realize the lies and kick her out. She has no plans or desire to work, improve her life, or provide for herself or her child.

In the past, she has set up GoFundMe accounts filled with lies about being homeless, sick, etc. She immediately takes that money and spends it on things like jewelry and nail polish.

Now to the part where our friends need advice. They would obviously like her to contribute, especially financially and in the material needs of her child. But they are afraid they have no power to force it and no leverage to use. They don’t want to simply kick her out because the 3 year old is safe and being provided for in their home and they don’t want her in the foster care system. And they can’t really give her money and tell her she can spend it on things like diapers and food, because she will just spend it on junk she doesn’t need.

How can our friends enforce some rules and contribution from their daughter without putting the 3 year old in danger of being taken away if they kick her mom out?

EDIT – what they’ve tried

• They’ve asked her to get a job. She won’t.
• They’ve sat down next to her and made her fill out job applications while they sit there. She only cooperates because they’re sitting there but she won’t follow through beyond that. She had a job for a few months before she ran away. She just stopped going. No warning/communication/notice to the company or parents. Just stopped. The day she stopped is also the day she ran away.
• They’ve looked into various single-mom homes and resources. These all have very limited space and strict rules and self-improvement goals that must be adhered to otherwise you’re be removed from the program. She has no interest in such a place nor desire to follow rules, be accountable to anyone, or better her life.
• They’ve asked her to help with certain chores/jobs around the house. She has some simple daily chores that can be accomplished in under 10 minutes a day. She rarely does these without being reminded and she grumbles every time. She has some rolling responsibilities on certain days and takes turns with the other children such as cleaning dishes and bathrooms. These she tends to do well and without complaint or prompt. She is responsible for watching her 3-year old and making sure she is properly supervised and cared for. She does this contentedly at a basic level. Keeps her daughter away from dangerous things, keeps her fed and changed, etc. But she feeds her daughter primarily "junk" food and the child is already ballooning at age 3 as a result. She also does not believe in any kind of discipline for her daughter. This has lead to the child becoming more and more unruly and disruptive to others in the household. There is also no effort to teach the child anything from the basics of education such as letters and numbers, to life skills such as putting toys away or not breaking things.
• They’ve tried talking with her on any number of things but she is extremely emotionally reactive. At the first hints of desired change in behavior or a reminder to do something she more often than not responds with an immediate outburst of anger, shouting and stomping away to her room.

The parents don’t feel they can make any demands to change behavior because they don’t see themselves having any leverage to use and the daughter has no desire to contribute more or make any preparations for her or her child’s future.

What the parents want in general order of priority:

• The safety and well-being of the child. This is most important to them and why they chose to remain in this situation
• Have her get a job and proper daycare for the child
• Have her not be verbally abusive to other children. She is mean and berating to one of the other children in particular.
• Better parenting of the child: discipline, better diet, teaching
• Pay for damages done to property (She has done considerable damage to her room due to neglect, slobbishness, etc.)
• Get a monthly room/board payment if she stays
• Be remunerated for previous expenses (clothing, diapers, food)

Ultimately they want her to be self-sustaining and living on her own.

In general the daughter’s behavior is worse than the parents consider acceptable to remain living there. The only reason they keep her is for the well-being and safety of her child. They’re not aware of any viable option for the child other than the foster system should her and her child leave. If it weren’t for the child they would require the daughter to leave.