In the fall of 2009, a young mother with a very sick child logged onto Twitter and began to vent her anguish. Lacey Spears’s son, whom she called “Garnett the Great” and “my little prince,” was sick again. “Hoping Garnett Does Have To Be Put In The Hospital :(,” she wrote one November day. Then two days later, she wrote: “My Sweet Angel Is In The Hospital For The 23rd Time.”

In the five years he lived, Garnett Spears would end up in the hospital many more times than that. The sicknesses were many: severe ear infections, high fevers, seizures, digestive problems. But their cause remained unclear until his final days, when doctors noticed a lethal amount of sodium choking his system. A doctor took Spears aside at the hospital. Those levels, the doctor reportedly said, were “metabolically impossible. … Something isn’t right.”

[Woman accused of fatally poisoning son in Munchausen case]

Despite those suspicions, the young woman at first seemed beyond duplicity. All you had to do was check her social media pages and blog to find how much she loved her son. The sites were festooned with messages that conveyed a dogged, resilient woman who somehow stayed positive despite her son’s travails. Spears gushed emotion like a geyser: “@ Work With My Little Prince!!! Couldn’t Be A Better Day!!! … Its About My Sweet Baby Boy & Me … If Anything Else Is Meant To Be It Will Be!!! … My son is my everything!!! I love him so much :).”

The confounding tale of her son’s strange demise came to a chilling resolution inside a Westchester County, N.Y., courtroom on Monday, when a jury convicted Spears of poisoning her child to death with heavy concentrations of sodium, which she administered through his stomach tube.

The defense and prosecution presented irreconcilable portraits of the 28-year-old woman of Scottsville, Ky. To her defenders, Spears was a dutiful mother caring for a very ill boy. To prosecutors, her motives were callous and calculated. She intended to make Garnett sick, and her actions were “nothing short of torture.”

“The motive is bizarre, the motive is scary, but it exists,” Patricia Murphy, an assistant district attorney, said during her closing argument, according to the New York Times. “She apparently craved the attention of her family, her friends, her co-workers and most particularly the medical profession.”

Lacey Spears, 28, is seen in an undated photo from the Westchester County District Attorney's Office in Westchester, New York. Spears, a single mother in New York state who documented the medical struggles of her 5-year-old son on social media, has been charged with murdering him by putting a toxic dose of sodium in his feeding tube. (Westchester County District Attorney's Office via Reuters) (Westchester County District Attorney’s Office via Reuters)

The seemingly incongruous portraits of Lacey Spears make sense, experts suggest, when filtered through the prism of a rare psychological syndrome called Munchausen by proxy, a disorder in which a caretaker or guardian purposely does harm to a child to attract sympathy and attention. “These mothers tend to be psychopathic,” Marc Feldman of the University of Alabama told CBS New York. “They don’t experience guilt and they lack empathy.”

But even that assessment, defense attorney Stephen Riebling said, doesn’t completely jibe with Spears’s actions. When her child was in the throes of his final sickness, hospital video captured one scene in which she put socks on her son’s feet when no one was around to see. “If she’s planning on killing him, why does she care whether his feet are cold?” he asked.

The answer could be that she never intended to kill him. She just wanted to make him sick.

Is that possible? “The purpose is not to kill the child but to keep her sick, so that the mother can be in a relationship with the doctor, who would recognize her devotion, knowledge and sacrifice,” psychiatrist Herbert Schreier of Children’s Hospital Oakland once told Psychology Today, speaking generally rather than about any particular case.

Spears’s lawyer did not use the syndrome as a defense in the trial and the subject did not come up in testimony, except in expert commentary in the media reports about her case. The child fatality report after the death reflected concern for Lacey Spears’s “emotional stability and it was presumed she suffered from Postpartum Depression and Munchausen Syndrome by Proxy,” Hudson Valley’s Journal-News said.

The syndrome has a long and contested history marked by adaptations to new technologies. Originally conceived as Munchausen syndrome, which describes someone who fabricates illnesses to curry sympathy with the medical community, a new branch of the disorder was introduced in a 1977 paper in the British medical journal the Lancet. Calling it the “hinterland of child abuse,” the article described patients who “by falsification, caused their children innumerable harmful hospital procedures.”

The syndrome came under criticism when the author of that study, a well-known British pediatrician named Roy Meadow, offered a wildly inaccurate statistical analysis during the trial of a woman suspected to have the disorder. His debunked assessment contributed to a lengthy prison sentence from which she later walked free and caused some to dispute his work. It just seemed too outlandish. Why on Earth would a woman purposely sicken her child?

But anecdotes kept coming. In 1999, a Florida woman was convicted of aggravated child abuse after she intentionally sickened her child and made her go through 40 pointless surgeries, reviving the specter of Munchausen syndrome by proxy.

For those afflicted by the syndrome, Feldman said, social media offers an almost irresistible avenue for sympathy. He called this additional vein of the illness “Munchausen By Proxy by Internet.” In the journal Child Abuse and Neglect, he described one woman he named “Ms. A” who joined an online community for pregnant women with a tale of woe. She claimed to have five children — two sets of twins and a niece she cared for after her sister’s death.

One of them, she told the group, was sick with gastroesophageal reflux and celiac disease. “Online friends offered sympathy and support,” but the whole thing was a ruse. “Ms. A” was actually a childless 21-year-old woman who “appeared to covet sympathy engendered by her deceptions.”

Similarly, Spears’s active online life turned out to be fantasy. On her blog, “Garnett’s Journey,” she invented Garnett’s deceased father, Blake, and spoke of doctor’s visits her behavior may have caused. But she could overcome the challenges, she promised, with the support of friends. “Healing takes courage,” she wrote, “and we all have courage, even if we have to dig a little to find it.”

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