Though Beyonce fired her longtime manager, Mathew Knowles, in 2011, she has never fully addressed her reasons for severing professional ties with her father, until now.

At the time, the singer's decision was rumored to have been a consequence of her parents' 2009 divorce, and subsequent reports that her Knowles had fathered a son out of wedlock with actress Alexsandra Wright.

In an hour-long interview with Oprah Winfrey, which will air on Oprah's OWN network just before Beyonce's Life is But a Dream doc premieres on HBO, Beyonce reveals that it was actually her relationship with her father, rather than his extramarital affair, which inspired her decision.

"It took a while for me and my dad to have an understanding. When I turned 18 and started handling my business more, he went into shock. And we had our issues. I'd say 'no' to something, and he'd book it anyway. Then I'd have to do it because I'd look bad [if I didn't]," Beyonce explains in the interview with Oprah.

"We would fight sometimes, and it took about two years, to when I was 20, for him to realize, 'Oh, she is an adult now, and if she doesn't wanna do something, I can't make her do it.'"

Check out a clip from the interview below, and watch the Oprah special in full on Feb. 16 at 8PM ET.

Watch Beyonce on Oprah's Next Chapter

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