Have you had a kidney reversal? Have question about it

My sister had acute kidney failure from strong meds used for a 3rd degree burn on her leg about 8 weeks ago. She was 100% healthy till that happened. She is 54 yrs old. She has been on dialysis 3 times a week for 4 weeks as of this writing. We are hopeful that her kidneys will reverse. Her creatinine level was at 8 and is now at 4 but the doctor said that is because of the dialysis treatments, and he said it has to reach 2 or below which shows the kidneys are working on their own. Anyone else ever had kidney reversal? if so, how long did it take you? My son's father in law got kidney shut down after heart surgery, but they reversed 2 months later. This happened to my sister 3 months after her husband retired. It has ruined everything for them including their bank acct. (she had no insurance at the time it happened), but we believe in God, and we are praying they reverse soon.