“On Thanksgiving, what’s always in the middle of the table?”/“The letter B.”

A Thanksgiving dinner table riddle is:
 
Q: On Thanksgiving, what’s always in the middle of the table?
A: The letter “b.”
 
The riddle has been cited in print since at least 2009.
 
     
BrainDen.com—Brain Teasers
Guests
Posted November 25, 2009
Happy Thanksgiving Everyone…..
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5. On Thanksgiving, what is always in the middleof the table?
   
123Friendster (April 22, 2011)
Thanksgiving Riddles
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Thanksgiving, what’s always in the middle of the table?
The letter “b.”
 
DESIComments.com (May 2, 2011)
Thanksgiving Riddles
Thanksgiving, what’s always in the middle of the table?
The letter “b.”
 
Twitter
Bill Helton
‏@7colonel7
Corny joke left over from Thanksgiving…On Thanksgiving what is always in middle of table?  The letter b!
11:34 PM - 16 May 2011
 
Parks & Recreation (City of Manassas Park)
DC KNOWS THANKSGIVING
Posted on November 28, 2011
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I asked Carl on Thanksgiving what’s always in the middle on the table. He said the letter “b”. Those new guys are really smart!