My mother-in-law broke her ankle. Will anyone pay for someone to stay with her until she is well?

I agree she should go to a NH that does therapy. If you spend 3 days in the hospital Medicare gives you 21 days covered at 100%. That is the only way to do it.

She would be best off in rehab, where whe can heal and receive therapy. One on one personal 24 hour companionship is very expensive, so it requires that she have insurance or can private pay. Even some programs cover assistance, but 24x7 is a lot.
Rehab is covered under Medicare, if it is medically necessary. There is a lot of value to get her walking well also to work on any of the residual effects surgery on the elder kind......it really could be best for her....it is only temporary.