Kelli Underwood, 46, a single mother of three, was found stabbed and shot to death in her Princeton, Texas, home in September 2017. Her daughter was the first to discover the crime scene when she went to check on her.While investigating the murder, the Texas Rangers found evidence that suggested that Underwood was involved in a love triangle and was murdered by hired hitmen. Four individuals, including the victim's former boyfriend and boss Ronnie Welborn and his then-girlfriend, were eventually arrested and convicted of the killing.The murder-for-hire plot is slated to feature on ID's Mean Girl Murders this April 3, 2023, at 9 pm ET. Titled Desperate Texas Housewives, the episode will delve into the tale of betrayal and a twisted love triangle. The synopsis of the episode states:"Bitter accusations unleash after single mom Kelli Underwood moves in with her best friend from high school; Kelli's daughter finds her dead, and investigators begin to uncover secrets and betrayals among the women of a small Texas town."Kelli Underwood's neighbors reported seeing two men at her house before she was found shot and stabbedJames Rose@JamesRoseOA#FOX4News: Kelli Underwood's family are pleading for the public to call in tips about the murder of the mother of 3 in Princeton last Week44#FOX4News: Kelli Underwood's family are pleading for the public to call in tips about the murder of the mother of 3 in Princeton last Week https://t.co/0qw2enj77QBorn and raised in Mesquite, Texas, just east of Dallas, Kelli Underwood married young but ended up as a single mother of three after two failed marriages. According to Oxygen, her daughter, Kayden Graham, described her as "a very positive person" whose "smile would light up a room."In 2001, Underwood was diagnosed with a life-threatening brain tumor. Following its removal, she suffered partial paralysis and battled depression. She soon moved in with her high school friend Tiffany Welborn in Dallas. She also started working in a metal fabrication business owned by her friend's husband, Ronnie Welborn. Underwood later dated Ronnie after the couple's divorce.Noelle Walker@NoelleNBC5Who killed Kelli Underwood? #Princeton police are looking for help. Her family is looking for answers, justice & closure. Watch 10p @NBCDFW31Who killed Kelli Underwood? #Princeton police are looking for help. Her family is looking for answers, justice & closure. Watch 10p @NBCDFW https://t.co/sp7wIsBfUyIn the spring of 2017, Kelli moved into a new home in Princeton, where she was found dead on September 20 by her daughter Kayden Graham, who went to check on the 46-year-old after failing to get in touch with her for days. Underwood was found on the floor of an upstairs room. An autopsy later confirmed that she died of multiple gunshots and stab wounds.While canvassing the crime scene, authorities found and collected five .22-caliber shell casings, silverware, a camera monitor, and cigarette butts in the backyard. They also collected DNA samples from beneath Underwood's fingernails. Her neighbors also confirmed seeing two men at her house who were working for her on September 16.Was a jealous love triangle the reason behind Kelli Underwood's death?Monica Hernandez@MonicaTVNewsPolice say Kelli Underwood was shot to death in her Princeton, TX home as part of a murder-for-hire prompted by a jealous love triangle. 4 people arrested. Exclusive intvw with police chief at 5.1012Police say Kelli Underwood was shot to death in her Princeton, TX home as part of a murder-for-hire prompted by a jealous love triangle. 4 people arrested. Exclusive intvw with police chief at 5. https://t.co/HBezuBVC9iInvestigators then spoke to Ronnie Welborn, who claimed that a friend and former employee named Robert Veal was one of the men working for Kelli Underwood at the time. They also learned about the victim's romantic relationship with Welborn. Family members confirmed that their secret relationship soured after Welborn started dating a younger woman, Kadie Robinson.Robinson soon became pregnant and moved in with Welborn, which led to a twisted love triangle between the three. Underwood had reportedly broken things off with Welborn, but the love triangle continued, given that she still worked for Ronnie, which highly troubled Robinson. Robinson and Welborn claimed no involvement in the murder and provided alibis.Natalie Solis@Fox4NatalieUPDATE: 4 ppl charged in murder-for-hire plot. Victim was 46yo mother of 3 Kelli Underwood of Princeton @FOX4119UPDATE: 4 ppl charged in murder-for-hire plot. Victim was 46yo mother of 3 Kelli Underwood of Princeton @FOX4 https://t.co/p3Z3lvm0m3The investigation took a shocking turn after one of Underwood's neighbors identified the second man present at her house as Delvin Powell before the killing. Powell had an extensive criminal history, and investigators also found knives and a box of .22-caliber ammunition in his possession.Both Veal and Powell claimed that Underwood was alive when they last met her, but investigators found digital evidence which suggested otherwise. Robinson later confessed that Welborn hired both men to kill the victim. Wellborn later "took all of the responsibility," claiming that he had her killed to put an end to the drama. Robinson was also implicated in using text messages she sent to the hired hitmen.All four individuals were convicted and sentenced to prison in connection with Kelli Underwood's murder.ID's Mean Girls Murders airs with the case this Monday, April 3, 2023.