Sebastian grew very bored with his role in Family Affair which led to him taking time off from the show. In order to compensate for his absence he was temporarily replaced by actor John Williams who portrayed the brother of Sebastian's character.
Sebastian's most famous trade mark was his prominent beard.
Sebastian's daughter, Annette, appeared with him in the episode The Flip Side on the TV show Family Affair.
In 1968 Sebastian was nominated for an Emmy Award for Outstanding Continued Performance by an Actor in a Leading Role in a Comedy Series for Family Affair (1966). In 2004 Sebastian won the TV Land Award for Best Broadcast Butler in the TV series Family Affair (1966).
Once Sebastian decided to become an actor, in order to receive his first roles, he claimed to have performed various roles he heard discussed by his previous employer actor Frank Pettingell and his friends.
After the second World War ended, Sebastian worked for the BBC as an expert in dialects.
Though Sebastian specialized in elegant and upper-class, educated roles, he was actually born a Cockney.
Sebastian recited Bob Dylan songs on the Album Sebastian Cabot, actor/Bob Dylan, poet.
As soon as Family Afair ended, Sebastian was quick to appear on talk shows and a game show in order to avoid being typecast by his role as the butler on Family Afair.
Once the TV series Family Afair ended Sebastian was quoted saying that both he and Brian Keith were extremely bored for the last two seasons of the show.
Sebastian originally didn't want to participate in the pilot of Family Affair (1966) as he didn't like the writing nor the role offered to him. However, as the salary he was offered for his participation was quite high he accepted the role.
For Sebastian's role as Kris Kringle on Miracle on 34th Street he had to shave off his famous beard and wear an artificial one after the makeup artists were unable to whiten and fill his real beard out so that he looked like Santa Claus.
Sebastian loved cars from an early age and when in his fifty's still spent a lot times tinkering with them and their engines.
Prior to becoming an actor, Sebastian found employment in the following professions:
He spent three years as a professional wrestler in London before the Second World War. He ended up quiting the profession after receiving an injury. He worked as a chef and it was during this period of time in which he gained weight and ended up weighing around 260 pounds. He also worked as a chauffeur for, British actor, Frank Pettingell. It is this job that actually got him interested in acting.
Sebastian made his stage debut in London in 1945, after the war had ended, in the play A Bell for Adano. He was 27 years old at the time.
Sebastian entertained the troops during the Second World War.
As per his request Sebastian was cremated upon his death. Sebastian is interred in the urn garden in Westwood Village Memorial Park Cemetery in Los Angeles, California, near his friend and fellow actor, Brian Keith.