I found several newspaper articles about Cathere Groocock at FindMyPast.com. Here is a summary:
Yorkshire Post and Leeds Intelligencer, July 30, 1872. Catherine Groocock poisoned her child, Kate Groocock, 17 months old, and then attempted suicide. The child's father was Henry John Groocock of Leeds. The child was poisoned with "Battle's Vermin Killer," which contained strychnine among other ingredients. The Coroner's jury found that the child died of willful murder by her mother.
Another article describes the trial, Leeds Mercury August 9, 1872. A witness, a cousin, stated that Mrs. Groocock's sister, a Mrs. Blackburn "went wrong in her head, her father also became insane, and another sister, a Mrs. Howarth, died raving mad."
Yet another article, Yorkshire Post and Leeds Intelligencer August 9, 1872, stated that she was found at trial to be suffering from religious mania and was acquitted on the ground of insanity.
(corrected minor typos)