A nanny who tried to poison Ann Summers boss Jacqueline Gold by lacing her asparagus soup with screenwash has been jailed for 12 months.
Allison Cox, of East Grinstead, West Sussex, admitted administering poison with intent to annoy last month.
Cox, 33, was hired by lingerie tycoon Ms Gold, 50, to look after her child at her home in Whyteleafe, Surrey.
Guildford Crown Court heard Cox was trying to get the chef who prepared the soup into trouble.
The court was told how she laced two bowls of asparagus soup with the toxic substance on 5 October last year.
She also put sugar and salt in Ms Gold’s meals on two other occasions, the court heard.
She was sacked immediately and arrested by police the next day.
Prosecutor Rachel Davies said Ms Gold had treated Cox as “part of the family” whom she trusted with “the most precious thing in her life, her daughter”.
She said that drinking the screenwash could cause nausea, gastrointestinal problems and even heart failure.
Tim Leete, for the defence, said Cox was of previous good character, had no previous convictions and had admitted what she had done immediately.
Judge Christopher Critchlow said Cox had demonstrated “calculated and deceitful behaviour” as well as breaching the trust of her employer who had entrusted her to look after her only child.
He said the experience had been “extremely distressing and traumatic” for Ms Gold, made all the worse because the child’s twin had died aged eight months.
“You had no idea whether or not that screen wash would cause harm to her or what the effect would be,” he added.
“This behaviour is a gross breach of trust as well as being totally bizarre.”
The judge said it was unlikely that the mother-of-one would ever find work as a nanny again.
Ms Gold is known as one of Britain’s most successful businesswomen with a reputed fortune of about £180m.