My fathers insurance only pays 15 days inpatient therapy. How do I get more time?

My father fractured his leg in four places in a fall, also dislocating ankle. he has private insurance that will only pay 15 days. He thinks he is going to be able to just come home with some minor modifications. He had fall issues before this. He lives alone in a 2 story home. He has long term care but it doesn't start until 90 days. I am totally disabled from a work accident but able to do some things for him. I am also the primary care giver to my 9 year old son as my wife works 6 days a week. He is a Korean war veteran but never applied for any benefits. His financial situation is okay as far as normal circumstances but if he has to pay a month or two of inpatient therapy it's going to wipe him out.