Was he the result of a one night stand?
I found this:
"The exact ethnicity of Vin Diesel is unknown. The mother of Vin Diesel has Scottish, English, and German ancestry. Although he is said to be part African-American, the actor is unaware of his biological father, and his mother isn't sure of his father’s full ethnic background."
Sounds like she didn't get a good look at the fella as they did it.
Some say he's part black, I actually think that if his mother is white European, his father may have been afro-latino.
He has a Cuban look, which is a mixture of Spanish and African blood.
I wonder if his biological father even knows he's alive?