Willie Nelson has had a complicated personal life in the past, and it caught up to him after his daughter Paula was born. In his new book, Nelson reveals the unpleasant moment when he had to tell his second wife, Shirley, that he had fathered a child with another woman.

The 87-year-old country legend says he "tried to play it off as no big deal" when Shirley saw a bill from a hospital in Houston, Texas. He told her he'd visited the hospital for something minor, but she "wasn't buying that for one simple reason: The bill said the charges were for the birth of a baby girl, Paula Carlene, born to a Mrs. Connie Nelson," he writes in a new memoir, Me and Sister Bobbie: True Tales of the Family Band, which he co-wrote with his sister and longtime musical collaborator, Bobbie Nelson (quote via People).

When his then-wife demanded to know who Connie Nelson was, the county singer says he "couldn't lie. Was caught flat-footed. Had to get the words out of my mouth. 'Connie’s my girlfriend and Paula's our daughter.'"

According to People, Nelson was married to his first wife, Martha Matthews, from 1952 until 1962, and they had three children. He married his second wife, Shirley, in 1963, and they divorced in 1971, after which he married his third wife, Connie Kopeke. They already had daughter, Paula, at the time, and subsequently had another daughter before they divorced in 1988.

Nelson met his fourth wife, Annie, when she was working as a makeup artist on Stagecoach, a 1986 film he starred in with Johnny Cash, Kris Kristofferson and Waylon Jennings. Their relationship brought about the end of his third marriage, he says in the book, writing, "My wandering ways were too much for any woman to put up with."

"I regret the pain I caused Connie — and Martha and Shirley before her — and have no excuses," Nelson admits. "But love is love, and in the mid-'80s, I fell head over heels in love with Ann Marie D'Angelo, called Annie. Never had met a woman like her before."

Nelson married D'Angelo in 1991. They're still together today.

"You've already seen that, when it came to romance, I had a gift for complicating things. But marrying Annie wasn't complicated at all," Nelson writes. "It's about the smartest thing I ever did. I can say that because, 34 years after we first met, we're still together and going strong."

Me and Sister Bobbie: True Tales of the Family Band was released on Sept. 15.

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