This 2007 article about Christopher and Jonathan Cerf selling their family's New York townhouse seems to be reliable.
They sold it after their mother Phyllis died. The address in Manhattan is 132 East 62nd Street. That's between Park Avenue and Lexington Avenue.
You will notice in the article that the buyer has a son who is a singer / songwriter, but many people don't know who he is. His songs don't get on terrestrial radio. That issue affects any possible revival of What's My Line? on television. The Live On Stage version with J. Keith can avoid indie artists if it wants to, but any show that reaches a nationwide audience claiming that anyone can go on it had better live up to that claim. Otherwise it fails or it becomes pathetic like the syndicated What's My Line? during its awful last season. During an episode videotaped in December of 1974 a used car salesman dumped a slew of business cards over Soupy Sales' head. Either you settle for that or you practice diversity.
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