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IMDb Biography for Thomas A. Edison
"Enjoyed communication with Morse Code so much, that he proposed
marriage to his girlfriend in it, and nicknamed his children "Dot" and
"In 1871 two important events happed: Edison's mother died, and later
that year, on Christmas day, he married Mary Stilwell, a former
employee. Their first child, Marion, was born in February 1873; their
first son, Thomas, Jr., in January of 1876 (these two were nicknamed
Dot and Dash by their father)..."
thomas edison children nicknames