Tesla Inc (NASDAQ:TSLA) CEO Elon Musk said his father Errol ran out of money in the ’90s and was provided financial support by the entrepreneur and his brother.

What Happened: Musk’s comments came on a Twitter thread that began with the Tesla CEO lambasting Berkley professor Robert Reich for asserting that the Musk family owned an emerald mine in Apartheid South Africa.

“Errol ran out of money in the 90’s. My brother & I financially supported him & his extended family in South Africa since then on the condition that he not do bad things. Unfortunately, he did do bad things,” said Musk on Twitter.

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Why It Matters: Musk had labeled Reich an “idiot and a liar” on Wednesday after the former Secretary of Labor posted a video questioning the self-made status of billionaires. In the video, Reich claimed that Musk came from a “wealthy family.”

In August, Errol said on an Australian radio show that Elon’s brother Kimbal was his “pride and joy.” The senior Musk also shared some insights into the family’s early life and said had taken his children around the world when they were still young.

When Errol was asked if he was proud of Elon, said, “We are a family that have been doing a lot of things for a long time. It's not as though we suddenly started doing something.”

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