Duck Dynasty patriarch Phil Robertson recently found out that he has a 45-year-old daughter from an affair he had in the 1970s — after he married his wife of more than five decades, Miss Kay.

The 74-year-old head of the Robertson clan revealed the news on Thursday (May 28) alongside his sons — Al, Jase, Jep and Willie — during an episode of their Unashamed podcast, as People reports.

Al explains that he first received a letter from a woman named Phyliss, who claimed to be his sister after taking a DNA test in hopes of finding her biological family. Phil Robertson married Kay in 1966, and he has admitted to infidelity on his part before he became a Christian in the 1970s, but his son initially dismissed the letter, since the woman's birth would have traced to after his father's conversion. As it turns out, he says it was just before he committed fully to his faith, which Robertson espouses very publicly.

Al adds that once he started looking at Phyliss' claim, he concluded "there might be something to this." Jase had also received a letter from Phyliss, and together they decided that this was not a frivolous claim like some of the other correspondence they've received over the years.

Al approached his parents, and Phil ended up being a 99.9 percent match with Phyllis after agreeing to take a DNA test. Phil says his reaction to finding out he is, in fact, Phyliss' father was to tell his sons to "bring her on down."

"We know that in all things — in all things — even sin, God works for the good of those who love him who have been called according to his purpose," Phil states, paraphrasing from the Bible.

The family have already met Phyliss, and Duck Dynasty fans can expect to meet her during an upcoming episode of the podcast. Instead of shaking the family, the Robertsons say the news is actually welcome.

"It was super awesome, I was so excited," says Jep, who always wished for a sister while growing up with all brothers. "It was like a dream come true."

"It's a pretty cool explanation of redemption, reconciliation, love," Phil Robertson states. "As it turns out, 45 years, you have a daughter that you don't know about, and she has a father she doesn't know about. 45 years, that doesn't sound like very long, but you say, that's a while. So finally, after all those years, we come together."

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