Robert Downey Jr. and Sammy Davis Jr. are arguably two of the biggest celebrities ever to rock nominal suffixes—but why aren't they Robert Downey II and Sammy Davis II?

Essentially, it's because they were named for their living fathers and not another close family member. Both of the nominal suffixes "Jr." and "II" refer to the fact that the person is the second in his family to have that exact moniker, including middle name. A "II" suffix typically specifies that the first person to bear the name wasn’t the namesake's father—the "II" likely honors a grandfather, a great-grandfather, an uncle, etc.

Women can also have the suffixes Jr. or II, but it's not as common, most likely because women historically took a new last name when they got married, negating the Jr. or II distinction. However, the daughter of fashion designer Carolina Herrera still goes by Carolina Jr., even though she has taken her husband's last name.

But back to one of our original examples: Interestingly, Robert Downey Sr. was also once a junior. The elder Robert Downey was born Robert Elias Jr., named after his dad. He later changed his name to his stepfather’s last name.

Of course, there’s always George Foreman, who has five sons named after himself. And since “Jr. Jr.” isn’t really a thing, George’s sons are George Edward Foreman Jr., George III, George IV, George V, and George VI. (Don’t worry; they all have nicknames.)

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