Usually, there are homemakers who would come in and do a great deal of those things. A company can get paid for the certain number of hours that these tasks are being done. With that being said, I would be clearer on what my role is. If you are finding you are cooking and cleaning more than taking care of the patient, I would bring it to your company, and ask that a homemaker be added a certain number hours a week/day. I would also do this if I was spending considerable time on PT/OT or any other non-nursing discipline--yes, nurses do ROM and assisted ambulation that type of thing, however, if I were doing what a PT person does for lengths of time, that would become an issue, as I am a nurse, not PT.
Another aspect of this is that you could "educate" the mother about how to take care of her childs' needs as far as food, cleaning, laundry and such. Education is also a huge part of what nursing is about.
I am curious if you have a case manager, and if you have meetings regarding your cases. If so, I would most definetely advocate for the child to have as much help in the house as possible. You are one person, you can't be everywhere at once, and although I think that keeping your patient's area clean and tidy is part of it, folding the family laundry and preparing meals and cleaning the house may not be.
I would have conversation about this with your manager. If the patient's insurance company is being billed for multiple disciplines that you are completing yourself, I would have to weigh what I am making for a wage against what I am tasked to do and see if it is worth it, or perhaps a job that has more boundries.
And I agree with the PP--I would review what it is that you are bound to do by the agreement signed,