Kaitlyn Conely was sentenced to 23 years in prison after poisoning her ex-boyfriend's mother. At the sentencing, the poisoned victim's widower, William Yoder, retold accounts of how his wife had spent her final hours vomiting and suffering from diarrhea.

Just hours before those symptoms appeared, William said that his wife appeared to be the picture of health, according to The State report.

"To get even with my son, she decided to murder his mother," William was quoted in a report. Conley and Yoder's son were involved in a years-long, off-and-on romance.

Conley spoke during her sentencing in Oneida County, New York, Court, saying that she is innocent, with all respect to the justice system. In addition to her prison term, Conley will be under five years' post-release supervision, according to a People report.

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Mary Yoder's Poisoning

Mary was a 60-year-old chiropractor with a thriving upstate New York practice that she ran with her husband.

 A friend who had seen her that day recalled Mary radiated her signature warmth and peace. However, this changed after lunch time when she started feeling sick and struggled to finish her scheduled appointments.

Mary then told her husband that she had a stomach bug, but she was brought to the hospital the next day, where doctors expected her to be released after an overnight stay. However, her condition worsened, according to an Oxygen report.

William then called their three children and summoned them to the hospital. Mary went into cardiac arrest and her death was painful and sudden.

Mary's longtime friend and client, Sharon Groah, asked what happened. An autopsy offered little answers and a closer look suggested Mary was poisoned.

A series of tests were then ordered to search for the presence of toxins, which includes arsenic, cyanide, and other standard poisons. However, the result came back negative after a number of weeks.

A poison control expert suspected Colchicine, which is an anti-gout drug with a narrow therapeutic index. This means that the range between therapeutic and toxic doses is small, and in some cases they overlap.

Oneida County Asst. D.A. Laurie Lisi said that in its pure form, a tiny amount is deadly. The lab results then revealed that Mary had a lethal amount of Colchicine in her system despite not having a history of gout.

Investigation for Suspicious Death

Detective turned their investigation to Mary's husband, William, and looked into the victim's life insurance policies as a potential motive. The search showed that nothing was suspicious and the possibility of an insurance payout as a motive was ruled out.

However, in November 2015, the case turned into a different way when the detectives received an anonymous letter mailed to the Oneida Country's Sheriff Office and blamed Adam Yoder, the couple's son.

The letter cited that Colchicine and said that a container of it could be found under the passenger seat of Adam's Jeep.

In December 2015, he was brought in for questioning and denied allegations about her mother's death. Investigators asked if they could search his vehicle and Adam gave them a go signal after consulting with a lawyer.

Detectives then spoke to on-off girlfriend, Conley, after doing some digging to Adam's whereabouts at the time of his mother's poisoning. Conley then admitted to writing the letter when police interviewed her and claimed that she was afraid of Adam.

Investigators lacked a clear connection between Conley, as well as a finding a motive as Mary was Conley's boss and a friend.

However, in February 2016, they found Conley's DNA on the Colchicine vial found in Adam's jeep.

"I hate the defendant with every bone in my body and every drop of blood in my veins," Adam was quoted in a report as he said during the hearing.

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