Speaking to The Sun, Musk Sr. said the second child was "unplanned" but that they are now all living together.
He said: "I haven't checked her DNA. But she looks just like my other daughters. She looks like Rose and Tosca mixed up.
Musk Sr. spoke about his relationship with BezuidenhoutGianluigi Guercia/AFP via Getty
"She looks exactly like Rushi and she behaves like him. So it's pretty obvious you know."
Musk Sr. added: "She wasn't planned. But I mean, we were living together. She [Jana] stayed here for about 18 months after Rushi was born.
"But I realised she's two generations behind whereas her mother was one generation behind when I married her. So any man who marries a woman, even if you feel very sprightly, it's going to be nice for a while. But there’s a big gap… And that gap is going to show itself.