You hire a forensic accountant to determine the worth, including business reputaion and "good will", future earnings, etc.
It gets hard to do with medical practices, & law practices b/c of reputation evidence, and family businesses are hard too. I'd never mix them again, fyi.
Forensic accountants are not cheap but they have value. And if I were you I'd at least consult one. So should she...
M: 57 H: 60 M: 35 yrs S30,D28,D19 H off to Alaska 2006 Recon 7/07- 8/08 *2016* X = "ALASKA 2.0" GROUND HOG DAY I File D 10/16 OW DIV 2/26/2018 X marries OW 5/2016