Patrica Ann Spann, 44, knowingly married her biological daughter, 26-year-old Misty Velvet Dawn Spann, in 2016, according to court records.
Under the deal, she was sentenced to 10 years of probation.
The defendant, who is from Duncan, was set to stand trial but instead entered a guilty plea Tuesday for last year's nuptials to mum Patricia Ann Spann.
The marriage was annulled October 12 after Misty filed for an annulment "by reason of illegality and fraud", She said her mother told her she had received legal advice indicating that their marriage was legal because Patricia's name was no longer on Misty's birth certificate. The blood relatives married in Comanche County, after filing their license application in March 2016.
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Cody Spann, one of Patricia's other children, says his siblings should not be punished and they were tricked into marrying their mother. In Oklahoma, incest is a felony. She was also once married to her son, who had the marriage annulled after claiming incest.
Patricia Spann, who is also charged with incest, is to appear in court in January.
What's perhaps most shocking of all is that this isn't the first time Patricia has been caught in a romantic relationship with one of her children.
KOCO 5 reported Patricia's marriages to her children were "all ploys to manipulate state laws".
Patricia Spann said that she didn't think the nuptials broke any laws because she was no longer listed as a parent on her daughter's birth certificate.
"For you to want to put your own daughter through this, what kind of person are you?" The marriage was annulled in 2010 due to "incest", The Associated Press reported.