Duck Dynasty's Robertson family like to tout their strong religious convictions and family values, but they're not above admitting that they're just like everyone else and that they too have sinned.

Phil Robertson's wife of nearly five decades has revealed to Us Weekly that their first child was born out of wedlock!

Miss Kay told the magazine, "Well, this is the first time I've shared this, aside from giving my testimony [in church]. When I made a vow to God and to [Phil], it was March 22nd, 1964." She was 16 at the time. However, the couple waited another four years to wed officially. She says, "We didn't do the legal papers until April 11, 1968, after Alan, my oldest, was born. Alan says, 'Yeah, I would be the B [bastard] in the family.'"

Miss Kay added, "But I want to tell you something. My heart and my vow to God was true from the first day."

In addition to Alan, Kay and Phil have three other sons -- Jase, Willie and Jep.