Once when Groucho was sidelined with appendicitis Zeppo played Groucho's part on stage and no one knew it was a different Marx Brother. Groucho claimed that his brother was better, giving him incentive to get well.
Zeppo was in an early silent Marx Brothers film which was never released. All copies of it have been destroyed.
The Marx Brothers, as a group, were voted in at #62 on Entertainment Weekly's "Greatest Movie Star of all time" list.
Zeppo founded a theatrical agency, along with his brother, Gummo, after leaving the Marx Brothers act.
He invented a wrist watch that constantly monitored cardiac patients' heart rate.
A newspaper article claimed that Zeppo appeared in a movie without his brothers but no copy of that film is known to exist.
His second wife was Barbara Blakeley, who later married Frank Sinatra.
His company developed and manufactured a clamp, called a "Marman Clamp" or "Marman Ring" that is used in nearly every moving vehicle.
Zeppo was the youngest of five brothers.
The Marx Brothers were given an honorary Academy Award in 1974 which Groucho accepted on his brothers' behalf.
At the time of his death, in 1979, Zeppo was the last surviving Marx Brother.
Zeppo was president of the Marman Manufacturing Company, which produced a type of motorcycle called the "Marman Twin".
In 1977 The Marx Brothers were inducted into the Motion Picture Hall of Fame.
After his death, his body was cremated and his ashes scattered at sea.
Zeppo had two sons, both adopted, Timothy and Bobby.