Turns out there isn't one:
"Missouri mom pleads guilty to killing family with antifreeze" Associated Press January 21, 2016
SPRINGFIELD, Mo. — A southwest Missouri woman has admitted to plotting with a daughter to fatally poison her husband and son and attempt to kill another daughter over a 14-month period.
Diane Staudte, 53, of Springfield pleaded guilty Thursday to one count of first-degree murder, one count of second-degree murder, and one count of first-degree assault, The Springfield News-Leader reports. Another daughter, 25-year-old Rachel Staudte, pleaded guilty earlier to helping with the poisonings at her mother’s insistence.
As part of a deal with prosecutors, Diane Staudte will avoid a possible death sentence. She faces a sentence of life imprisonment without the possibility of parole.
Staudte told investigators that she poisoned her 61-year-old husband, Mark Staudte, with antifreeze because she hated him, and that she killed her 26-year-old son, Shawn Staudte, because he was “worse than a pest,” according to the probable cause statement. She also admitted poisoning her daughter Sarah Staudte over four days.
A medical examiner initially ruled that her husband’s April 2012 death was from natural causes and her son’s September 2012 death was from prior medical issues. But a tip led authorities to re-examine the deaths in 2013.
Also see: Ferguson, US reach tentative deal on police overhaul