As a result, they broke up in 1979, but remained close friends. Then in 1984 they renewed their romance, and in November 1985, they married, already having had a son, Max Samuel. After three and a half years of marriage, however, many of the same competing stresses of their careers caused them to divorce in 1989. They agreed to maintain homes near each other as to facilitate the shared custody and parenting of their son.:403 Their divorce was recorded as the third most costly celebrity divorce in history.

Answer this question, if possible (if impossible, reply "unanswerable"): Who was the husband in the most costly celebrity divorce in history?
unanswerable